21•3.14=65.94 the circumference is 65.94
Step-by-step explanation:
the number which is a perfect cube :
125, because 125 = 5³
Answer : B
the distance between the points (4,3) and (2,-1)
We apply distance formula

(x1,y1) is (4,3)
(x2,y2) is (2,1)


d^2 = 4+16 = 20
Take square root on both sides
So 
the distance between the points (4,3) and (2,-1) is 2sqrt(5)
We breakdown the components of the distances.
(1) 90 miles west.
x - component = -90 miles
y - component = 0 miles
(2) 80 miles, northwest (120°)
x - component = (80 miles)*(sin 30°) = 40 miles (negative)
y - component =(80 miles)*(cos 30°) = 69.282 miles (positive)
Solve for the distance,
√(-90 - - 40)² + (69.282 miles)² = <em>147.31 miles</em>