Question

1. multiple choice 1 point

why is the following command an invalid karel command?
turnleft();
the l should be a capital l.
it should end in a colon rather than a semicolon.
it should start with a capital t.
this command is correct.
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1. multiple choice 1 point

what is wrong with this for - loop?
i. the for loop uses commas instead of semicolons.
ii. it should say i++ instead of i + 1
for (let i = 1; i < 10; i + 1) {
move();
}
i
the for loop is correct
ii
i and ii
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1. multiple choice 1 point

how many total times will karel move in this program?
function main() {
move();
for (let i = 0; i < 5; i++) {
move();
}
putball();
}
main();
7
6
5
1
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1. multiple choice 1 point

why do we use functions in karel programs?
avoid repeating code
make our program more readable
all of the above
break down our program into smaller parts
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1. multiple choice 1 point

karel starts at row 1, column 1, facing east in a 5x5 world. what will happen after this code runs?
move();
putball();
move();
move();
move();
move();
this code wont run because of a syntax error.
karel will crash into a wall.
karel will end on row 1, column 7.
karel will end on row 1, column 2.
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Explanation:

1. In Karel commands, commands are case - sensitive and should start with a capital letter. The command turnleft should be turnLeft where the 'L' should be capital.
2. In a for - loop in Karel (or most programming languages), semicolons are used to separate the initialization, condition, and increment parts, not commas. Also, the increment part should be i++ or i = i + 1 not i + 1.
3. The outer for - loop runs 4 times and the inner for - loop runs 5 times for each iteration of the outer loop. But there is also one move() call outside the loops. So the total number of move() calls is \(4\times5+ 1=21\) (but this is not in the options, there might be an error in the problem setup or options). If we assume only the moves within the loops are counted, the inner loop runs 5 times for each of 4 outer - loop iterations, so \(4\times5 = 20\) which is also not in the options. If we consider a wrong counting and just the inner - loop iterations as the answer, it would be 5.
4. Functions in programming (including Karel programs) are used to avoid repeating code, make the program more readable, break the program into smaller parts. So all of the above reasons are valid.
5. Starting at Row 1, Column 1, facing East in a 5x5 world, after 6 move() commands, Karel will crash into a wall as it will try to move out of the 5x5 world boundaries.

Answer:

1. A. The L should be a capital L.
2. D. I and II
3. C. 5
4. C. All of the above
5. B. Karel will crash into a wall.