CSP Unit 4 Review

What number will be output by the console.log command on line 7?

• 10

• 100

• 20

• 200

Answer explanation

The variable bop is initialized on line 2. On line 3, the variable bop is assigned the value 10. On line 5, the variable bop is assigned the value 100. Since the most recent value bop has been assigned is 100, that is the value that will be printed by the command on line 7.

What number will be output by the console.log command on line 5?

• 10

• 11

• 12

• 13

• 16

Answer explanation

Walking through the program line by line:

On line 1, the variable oop is initialized and the value 10 is stored in it

On line 2, the variable oop is assigned its current value (10) plus 1.

On line 3, the variable oop is assigned its current value (11) plus 2.

On line 4, the variable oop is assigned its current value (13) plus 3.

On line 5, the current value assigned to oop, 16, is output.

What number will be output by the console.log command on line 5?

• 10

• 25

• 30

• 35

Answer explanation

Walking through the program line by line:

On line 1, the variable kit is initialized and assigned the value 20.

On line 2, the variable roo is initialized and assigned the value 10.

On line 3, the variable kit is assigned to its current value (20) plus 5.

On line 4, the variable roo is assigned to the current value of kit (25) plus the current value of roo (10).

On line 5, the current value assigned to roo, 35, is output.

What text will be output by the program?

• less than 10

• less than 20

• less than 30

• 30 or more

Answer explanation

Walking through the program line by line:

On line 1, the variable score is initialized and assigned the value 0.

On line 2, the variable score is assigned its current value (0) plus 10. On line 3, the variable score is assigned its current value (10) plus 10. On line 4, the variable score is assigned its current value (20) plus 10.

On line 5, the boolean expression score < 10 evaluates to false since the current value of score is 30, which causes the command on line 6 to not execute.

On line 7, the boolean expression score < 20 evaluates to false since the current value of score is 30, which causes the command on line 8 to not execute.

On line 9, the boolean expression score < 30 evaluates to false since the current value of score is 30, which causes the command on line 10 to not execute.

Since all of the if-else-if statements have evaluated to false, the command inside the else statement will run and the console prints 30 or more.

What text will be output by the program?

• Output A

• Output B

• Output C

• Output D

• Output E

Answer explanation

What will be the order of letters printed to the console when this program is run?

• a b c

• a b c b c b c

• a b c b c

• a b c a

Answer explanation

Line 1 will print out a, line 2 calls the function letters which will print b then c. Line 3 calls the function letters agan which will print b then c.

"You win!" never displays. What change would fix this issue?

• Line 1 - change variable name to totalScore

• Line 3 - remove var

• Line 4 - change conditional to score >= 5

• Line 5 - change to a getText command

Answer explanation

While it looks like there's only one variable being used, it actually has two variables, one local, and one global, and they're both named score. Every time button2 is clicked the local variable score is recreated and then deleted once the onEvent is done running. This means that the value of the local variable will never be greater than 5 and therefore the setText command inside the conditional statement will never execute.

When this function is called, the smaller of two numbers is displayed. What Boolean expression would not work in line 12 in order to accomplish this goal?

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Answer explanation

We can use the first call to the function smallest() to demonstrate why num1 == num2 would prevent the function from accomplishing its goal. The first time smallest() is called on line 3, the value assigned to num1 is 5 and the value assigned to num2 is 7. So walking through the function line by line:

The function would print What is smallest? 5 or 7? to the console.

The conditional statement 5 == 7 would evaluate to false.

The command under else will run and 7 is the smallest will print to the console.

This function chooses the screen to display based on the score. What is the correct way to call this function?

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Answer explanation

When calling a function, the name of the function must match the exact spelling and capitalization of the function definition.

There is repeated code in these onEvent blocks. Choose the correct code for the updateScreen() function which would be called in each of the onEvent blocks.

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Answer explanation

Since this setText command and conditional statement with a setProperty command appear in both onEvent blocks, these would be the appropriate blocks to include in the updateScreen() function. While there are similarities between other blocks that appear in both onEvent blocks, these are the only ones that are used identically in both.