How do you do q4 and what is the answer

Q 4

we know that a pie chart is a circle
we know that a circle is 360 degrees
so we multiply 7/10 with 360 and get the degrees
252 degrees

off topic, question 3 is wrong because if you want to round to 1 sig fig, you would look at the 100ths place to round to the 10th's place so 0.000 (disregard the 9 because it's too far away) rounded up =0