1. 156
2. 15.6
3. 1.56
You just move the decimal point in depending on the number or zeros.
Try this solution:
for the circle A: circumference=6π, area=9π
for the circle B: circumference=12π, area=36π
PS. formula for circumference is 'L=2πr', for area is 'S=πr²'.
If an ostrich can run 50 miles in one hour then he can run 12.5 miles in 15 minutes. 15 minutes is 1/4 of an hour. Multiply 50 by 0.25 = 15.
Convert it then you will fine the weight.