AP CSP Unit 3 Review

Front

Helpful actions in app design: I and III

Back

I and III only

Answer explanation

Consultation and communication with program users is an important aspect of program development. Incrementally adding tested program segments to correct working programs helps create large correct programs. You received feedback from your peers when you generated your idea. You also observed classmates using their apps last week.

Front

Purpose of a design specification (prototype):

Back

Describes requirements for program functionality and user interaction.

Answer explanation

We created a prototype of the app.

Front

Background color of topButton after execution?

Back

blue

Answer explanation

This is an example of sequential programming where the program statements run in order, from top to bottom. Since the last change to the “background-color” of the “topButton” is to the color blue, that is the color it will be when the program is done running.

Front

Color of 'topButton' if not clicked?

Back

blue

Answer explanation

Since this is an example of event-driven programming, the commands on lines 4 and 5 will only execute when the user clicks the “topButton” since they are inside the onEvent block.

Since this question asks about the situation of the user NOT clicking the button, the last change to the color happens when line 2 executes and sets it to blue.

Front

Program run, user clicks 'topButton' once. Console output?

Back

cat dog bird

Answer explanation

Once the program is run, lines 1 and 5 will run, in that order, right away, meaning that the first two words displayed will be cat and dog respectively.

The word bird will be displayed once the user clicks the “topButton” and causes line 3 to run.

Front

Program run, user clicks 'bottomButton' then 'topButton'. Console output?

Back

chicken pig cow

Answer explanation

Walking through the code run based on the description in the question:

Line 7 will run as soon as the program is run, displaying chicken to the console.

The user clicks the “bottomButton” ONCE which causes line 5 to run, displaying pig to the console.

The user clicks the “topButton” ONCE which causes line 2 to run, displaying cow to the console.

Front

Program run, user clicks 'bottomButton' twice. Console output?

Back

banana dragon fruit cherry cherry

Answer explanation

Walking through the code run based on the description in the question:

Lines 4 and 8 will run as soon as the program is run, in that order, displaying banana then dragon fruit to the console.

The user clicks the “bottomButton” the first time which causes line 6 to run, displaying cherry to the console.

The user clicks the “bottomButton” the second time which causes line 6 to run again, displaying cherry to the console again.

Front

Code line likely to cause an error:

Back

Line 2

Answer explanation

When printing characters to the console, they must have quotes around them to mark them as a string. Numbers can be printed as strings as in “100” or as numbers with no quotes, as in 100.

Front

Differences between sequential and event-driven programming: Sequential runs commands in order; event-driven runs some commands in response to events.

Back

Sequential: commands run in order. Event-driven: commands run in response to events.

Front

NOT a reason to include comments in programs:

Back

Comments help the computer decide if certain components are important.