Ursula and her friends are playing hoop rolling. Ursula rolls a large hoop along the ground. The hoop rotates through an angle of 3/2 times pi radians in 1 second. How many revolutioins does the hoop make in one minute?

1 revolution = 360 degrees
3/2pi = 1 second
1 revolution = 2pi radius
3/2pi (360/2pi)= 3/2pi (180/pi)=270 degree sec.