Calculate the area of a circle with a radius of 2 cm and a circle with a radius of 4 cm. leave your answers in terms of pi.

when the radius doubles, does the area of the circle double?
a) 4π cm2; 8π cm2; no
b) 4π cm2; 16π cm2; no
c) 4π cm2; 16π cm2; yes
d) 4π cm2; 8π cm2; yes

b. 1.25 hr

step-by-step explanation:

if you have a constant speed of 60 mph, then you have a ratio between 60 mi. to 1 hr. dividing both sides by 60 we get the ratio

1 mi. to

then mult. both sides by 75 we get the ratio

75 mi. to

simplifying we get

75 mi. to

or 1.25 hr.

the probability that a bird is green (.30) is true

step-by-step explanation: