Answer: Option 'C' is correct.
Step-by-step explanation:
Since we have given that

An arc is a part of total circumference of circle and length of that arc is the measurement of linear distance.
Since we know the formula for "Length of an arc " , we get

Hence, Option 'C' is correct.
Second one
1/16
3/8 divided by 1/6=1/16
Draw the number line then put the numbers on the number line by twos. Fore example, 2-4-6-8-10