Chapter 4 Decisions. Section 4.1 Relational and Logical Operators. 1. Asc("A") is 65. What is Asc("C")? (A) 66 (B) 67 (C) 68 (D) "C" B

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1 hapter 4 ecisions Section 4.1 Relational and Logical Operators 1. sc("") is 65. What is sc("")? () 66 () 67 () 68 () "" 2. sc("") is 65. What is displayed by txtox.ext = hr(65) & ""? () () () () Not enough information is available. 3. Which of the following expressions has as its value the words "Hello World surrounded by quotation marks? () "Hello World" () hr(34) & "Hello World" () hr(34) & Hello World & hr(34) () hr(34) & "Hello World" & hr(34) 4. Which of the following is true? () "at" = "cat" () "at" < "cat" () "at" > "cat" () Relational operators are only valid for numeric values. 5. Which of the following is a valid Visual asic conditional statement? () 2 < n < 5 () 2 < n Or < 5 () 2 < n Or 5 () (2 < n) Or (n < 5) 6. Which statement is true? () "ord" < "ord" () hevy > hevy () GM <= GM () oldsmobile < Oldsmobile

2 7. Which statement is false? () "ord" >= "ord" () "hevy" <= "chevy" () GM <= GM () Oldsmobile < Oldsmobile 8. he operator nd is a(n) operator. () arithmetic () relational () logical () none of the above 9. he three main logical operators are,, and. () nd, Or, Not () nd, Not, If () Or, Not, If () alse, nd, rue 10. When using the logical operator nd, what part of the expression must be true? () only the left part () only the right par () both parts () either the left or right part, but not both 11. When using the logical operator Or, what part of the expression must be true? () only the left part () only the right part () either the left or right part, but not both () either the left or right part 12. When is the expression Not cond1 true? () when cond1 is false () when cond1 is true () when cond1 is either true or false () None of the above 13. When Visual asic stops evaluating a compound condition with the logical ndlso operator because the first condition evaluates to alse, it is called evaluation? () short-circuit () pre- () compound () first

3 14. Which value for x would make the following condition true: x >= 5 () x is equal to 7 () x is equal to 5 () x is equal to () ll of the above 15. Which value for x would make the following condition true: Not (x >= 5) () x is equal to 7 () x is equal to 4 () x is equal to () ll of the above 16. Which value for x would make the following condition true: (x >= 5) nd (x <= 6) () x is equal to 7 () x is equal to 5 () x is equal to () and 17. "1st Place" < "2nd Place" (/) 18. he second condition in cond1 OrElse cond2 is not evaluated when the first condition is false. (/) 19. compound condition containing the keyword Or will always have the same truth value as the compound condition where Or is replaced with OrElse. (/) 20. he second condition in cond1 ndlso cond2 is not evaluated when the first condition is true. (/) 21. he following two statements are equivalent. (/) Not (a < b) a > b 22. In Visual asic, the letter j is considered to be greater than the letter y. (/) 23. he nd operator requires that both conditions be true for the compound condition to be true. (/)

4 24. If two simple conditions are true, the compound condition created from them by the Or operator is also true. (/) 25. he condition "Y" = "y" is true. (/) 26. If two simple conditions are true, the compound condition created from them by the nd operator is also true. (/) 27. he following condition evaluates to rue. (/) ("OG" > "") nd ("" > "IR") nd ("IR" > "aardvark") 28. ssume that,, and are conditions, with being true, being true, and being false. Give the truth value of ( nd (Not )). alse 29. ssume that,, and are conditions, with being true, being true, and being false. Give the truth value of ( nd Not ( or )). alse 30. ssume that,, and are conditions, with being true, being true, and being false. Give the truth value of (Not ( nd )). alse 31. Is the following condition true or false (assume a = 2, b = 3, and c = 3)? (a = c) Or (b = c) true 32. < and = are examples of relational operators. (/) 33. onditions can involve variables, operators, and functions. (/) 34. wo strings are compared working from left to right, character by character, to determine which one should precede the other. (/) 35. Write a condition to express each of the following: (a) X is strictly between 10 and 10. (X > 10) nd (x < 10) nother answer is Not (X >= 10 Or X <= -10) (b) Exactly one of X and Y is greater than 6. ((X > 6) nd (Y <= 6)) Or ((Y > 6) nd (X <= 6)) nother answer is ((X > 6) Or (Y > 6)) nd Not ((X > 6) nd (Y > 6)) (c) oth X and Y are positive or both X and Y are negative. (X >0 nd Y > 0) Or (X < 0 nd Y <0 ) nother answer is X * Y > 0

5 36. he value of "education".endswith("on") is rue. (/) 37. he value of "education".startswith("e") is rue. (/) 38. he value of IsNumeric("$20.00") is rue. (/) 39. he value of IsNumeric("wenty") is rue. (/) 40. he value of 1 <= n <= 9 is rue if the value of n is between 1 and 9. (/) Section 4.2 If locks 1. onsider the following two sets of code. (a) If (a = 1) nd (b = 1) hen (b) If a = 1 hen txtox.ext = "Hi" If b = 1 hen txtox.ext = "Hi" Which one of the following statements is true? () (a) and (b) will produce different outputs. () (b) is not a valid set of Visual asic instructions. () he two sets of code are equivalent, but (a) is preferred to (b) because (a) is clearer. () he condition statement in (a) is not valid. 2. What will be displayed by the following program when the button is clicked? Private Sub btnisplay_lick(...) Handles btnisplay.lick im a, b, c, x s ouble a = 5 b = 3 c = 6 If a > c hen x = 1 Else If b > c hen x = 2 Else x = 3 txtox.ext = Str(x) End Sub () 1 () 2 () 3 () None of the above

6 3. What will be the output of the following program when the button is clicked? Private Sub btnisplay_lick(...) Handles btnisplay.lick im x, y, z s ouble x = 3 y = 3 If x > y hen z = x + y Else z = y - x txtox.ext = Str(z) End Sub () 6 () 3 () 0 () No output 4. What will be the output of the following program when the button is clicked? Private Sub btnisplay_lick(...) Handles btnisplay.lick im word1, word2, newword s String word1 = "shower" word2 = "about" newword = word1.substring(0, 4) & word2.substring(0, 3) If newword.indexof("how") = -1 hen txtox.ext = "he new word was not found." Else txtox.ext = "ound it." End Sub () he new word was not found. () ound it. () Syntax error () No output 5. What will be the output of the following lines of code? im phrase s String = " penny saved is worth nothing." If phrase.indexof("pen") <> -1 hen txtox.ext = Str(phrase.IndexOf("pen")) Else txtox.ext = Str(-1) () pen () 2 () 0 () penny saved is worth nothing.

7 6. Which of the following is not a logical operator in Visual asic? () Not () nd () Or () hen 7. What will be displayed when the button is clicked? Private Sub btnisplay_lick(...) Handles btnisplay.lick im num s ouble = 9 im sqrroot s ouble If num < 0 hen Messageox.Show("annot find square root. Result set to zero.", "Error") sqrroot = 0 Else sqrroot = Math.Sqrt(Num) txtox.ext = Str(sqrRoot) End Sub () 0 () 3 () 6 () n error will occur. 8. (n) allows a program to decide on a course of action based on whether a certain condition is true or false. () Or block () If block () nd block () Else block 9. onstructs in which an If block is contained inside another If block are called: () multi-if blocks () nested If blocks () sequential If blocks () None of the above

8 10. What word(s) will appear in the list box when the button is clicked? Private Sub btnisplay_lick(...) Handles btnisplay.lick im num s Integer = 5 If num = 2 hen lstox.items.dd("wo") ElseIf num > 3 hen lstox.items.dd("great") ElseIf num = 5 hen lstox.items.dd("equal") End Sub () wo, Great, and Equal () Great and Equal () Great () Equal 11. When an If block has completed execution, the program instruction immediately following the If block is executed. (/) 12. he following lines of code are correct. (/) If (txtge.ext >= 62) hen txtoutput.ext = "You are elegible to collect Social Security." 13. he following lines of code are correct. (/) If age >= 13 nd < 20 hen txtoutput.ext = "You are a teenager." 14. he Else part of an If block may be omitted if no action is associated with it. (/) 15. Given that x = 7, y = 2, and z = 4, the following If block will display "RUE". (/) If (x > y) Or (y > z) hen txtox.ext = "RUE" 16. Given that x = 7, y = 2, and z = 4, the following If block will display "RUE". (/) If (x > y) nd (y > z) hen txtox.ext = "RUE" 17. Every If block must have a hen and an Else. (/) 18. No more than one ElseIf statement may occur in any one If block. (/)

9 19. No more than one Else statement may occur in any one If block. (/) 20. variable declared inside an If block ceases to exist after the block is exited. (/) 21. he following line of code is valid. (/) If letter = ("he quality of mercy is not strained").substring(7, 1) hen 22. he following line of code is valid. (/) If 0 grade 100 hen Section 4.3 Select ase locks 1. Why is the following Select ase block invalid in Visual asic? Select ase myname.substring(0, 1) ase myname < "" txtox.ext = "Your name starts with,, or." End Select () here should not be a standard conditional expression in a value list. () here are not enough ase statements. () here is no selector. () myname.substring(0, 1) is not valid where it is. 2. Suppose that the selector in a Select ase block is the string variable myvar. Which of the following is NO a valid ase clause? () ase "dams" () ase "739" () ase myvar.substring(0, 1) () ase myvar.length

10 3. What will be the output of the following program when the button is clicked? Private Sub btnisplay_lick(...) Handles btnisplay.lick im name s String = "Washington" Select ase name ase "George" txtox.ext = "George" ase "Wash" txtox.ext = "Wash" ase "WSHINGON" txtox.ext = "WSHINGON" ase Else txtox.ext = "Washington" End Select End Sub () WashWashington () Washington () WSHINGONWashington () No output 4. What is the problem (if any) with the following Select ase block which is intended to determine the price of a movie depending on the patron's age? Private Sub btnisplay_lick(...) Handles btnisplay.lick im age as Integer, price s ecimal age = Int(Inputox("Enter your age:")) Select ase age ase Is >= 65 'Senior citizen price = 4.50 ase Is >= 5 'Regular price price = 6.00 ase Is >= 0 'hild (no charge with parents) price = 0 ase Else txtox.ext = "Entry error" End Select End Sub () Everyone will get in free at the child rate. () he output will always be "Entry error." () he ase Is statements have bad syntax. () here is nothing wrong.

11 5. What will be the output of the following program when the button is clicked? Private Sub btnisplay_lick(...) Handles btnisplay.lick im a, b, c, acronym s String a = "federal" b = "aviation" c = "administration" acronym = a.substring(0, 1) & b.substring(0, 1) & c.substring(0, 1) Select ase acronym ase "" txtox.ext = "ederal viation dministration" ase "E" txtox.ext = "rug Enforcement gency" ase Else txtox.ext = "Unknown acronym. Sorry." End Select End Sub () ederal viation dministration () rug Enforcement gency () Syntax error () Unknown acronym. Sorry. 6. In a Select ase block, if more than one ase clause matches the selector, () only the statements associated with the first matching ase clause will be executed. () all of the statements associated with each matching ase clause will be executed. () only the statements associated with the last matching ase clause will be executed. () the program will malfunction and stop. 7. What will be displayed in the list box when the following code runs? Select ase num ase 6, 7, 11 lstox.items.dd("w") ase Is < 7 lstox.items.dd("x") ase Is > 5 lstox.items.dd("y") ase Else lstox.items.dd("z") End Select () Z can never be displayed. () W, X and Y will be displayed if the value of num is 6. () W and Y will be displayed if the value of num is 7. () Z will always be displayed. 8. ifferent items appearing in the same value list of a Select ase block must be separated by a. () semi colon () comma () colon () pair of quotation marks

12 9. Which ase clause will be true whenever the value of the selector in a Select ase block is between 1 and 5 or is 8? () ase 1 o 8 () ase 1 o 5, 8 () ase 1 o 8, 5 () ase 1 o 5; Which ase clause will be true whenever the value of the selector in a Select ase block is greater than or equal to 7? () ase Is >7 () ase Is = 8 () ase Is >= 7 () ase Is <= What type of items are valid for use in the value list of a ase clause? () literals () variables () expressions () ll of the above 12. he ase Else part of a Select ase block is optional. (/) 13. One may use an If block within a Select ase block. (/) 14. One may use a Select ase block within an If block. (/) 15. Every Select ase block can be replaced by If blocks. (/) 16. One may use a Select ase block within another Select ase block. (/) 17. Select ase choices are determined by the value of an expression called a selector. (/) 18. Items in the value list must evaluate to a literal of the same type as the selector. (/) 19. single ase statement can contain multiple values. (/) 20. You can specify a range of values in a ase clause by using the o keyword. (/)

13 21. variable declared inside a Select ase block cannot be referred to by code outside of the block. (/) Section 4.4 Input via User Selection 1. t design time, values can be placed into a list box via the. () String Editor () String ollection Editor () ollection Editor () Items Editor 2. collection of related radio buttons is usually placed in a. () List box () ext box () ollection Editor () Group box 3. What property gives the value of the index of an item selected in a list box. () Selection () SeletedItem () Index () SelectedIndex 4. he default event procedure for a list box is. () SelectedIndexhanged () lick () heckedhanged () Indexhanged 5. he default event procedure for a check box is. () SelectedIndexhanged () lick () heckedhanged () hecked 6. If the value of lstox.selectedindex is 0, then an item in the list box has been selected. (/) 7. licking on a selected radio button deselects the radio button. (/) 8. he index of the first item in a list box is 1. (/)

14 9. licking on a checked check box unchecks the check box. (/) 10. Which of the following statements selects the radio button radutton? () radutton = rue () radutton.on = rue () radutton.hecked = rue () radutton.selected = rue 11. Which of the following is not commonly used to allow the user to select among several options? () a collection of radio buttons () a collection of check boxes () a list box () a collection of text boxes 12.. he value of lstox.ext is the currently selected item of the list box. (/) 13.. When a check box is empty, the value of its Selected property is alse. (/) 14. Which of the following techniques does NO always toggle the checked and unchecked state of a check box control? () lick on the square or its caption with the mouse. () Press the spacebar when the square has the focus. () Press lt+ccess key (if an access key has been specified). () Set the hecked property equal to Which of the following techniques always toggles the "on" and "off" states of a radio button control? () lick on the circle or its caption with the mouse. () Press the spacebar when the circle has the focus. () Press on another radio button in the same group box. () Set the hecked property equal to rue. (E) None of the above E 16. What is the key difference between a group of check boxes attached to a group box and a group of radio buttons attached to a group box? () Only radio buttons can be toggled. () Only one radio button at a time can be checked. () heck boxes cannot be attached to a group box. () he only difference is the shape of the control.

15 13. When a check box is checked, the value of the hecked property will be () rue. () alse. () 1. () he title (as seen by the user) for the group box control is set by which one of the following properties? () ext () Name () ag () nchor 15. When the user clicks on a check box control at run time, which one of the following events is raised (in addition to the lick event)? () ontroldded () Invalidated () Stylehanged () heckedhanged 16. check box control named chkirst contains the following code in its heckedhanged event procedure. Which of the following is true concerning the use of this control? im message s String = "hello" Messageox.Show(message) () he message "hello" will appear when the user checks the control but not when it is unchecked. () he message "hello" will appear when the user unchecks the control but not when it is checked. () he message "hello" will appear when the user checks the control and again when it is unchecked. () he message "hello" will not appear using this code. 17. Suppose there are four radio button controls attached to a group box control on a form. How many radio buttons can be selected (that is, be on ) at any given time? () 2 () 1 () 3 () 4

16 18. radio button named radutton is placed on a form, and the statement Messageox.Show(radutton.hecked) is placed in its heckedhanged event procedure. t run time, what result will be displayed in the message box when the user clicks on radutton? () 1 () rue () 2 () alse 19. fter several controls of the same type have been created, they can be moved inside a group box and thereby become attached to it. (/) 20. With a check box control, toggling the state of the small square raises the heckhanged event. (/) 21. Group boxes are passive objects used to group related sets of controls. (/) 22. Programmers frequently write event procedures for the group box control. (/) 23. If you set a group box control s Visible property to alse, the attached controls will still remain visible. (/) 24. When a check box control has the focus, the spacebar can be used to invoke its heckedhanged event. (/) 25. s with the button and check box controls, an access key can be set up by placing an ampersand in front of a letter in the radio button s ext property setting. (/) 26. Suppose a form contains two group box controls with one radio button placed on each. In this case, both radio buttons can be selected (or turned on ) at the same time. (/)