Angle measures, arc length and revolutions

1.  The angle is just arc length/radius:  angle = 8/2 = 4 radians

 

2.  arc length = angle*radius:  arc length = 5*pi inches

 

3.  angular speed = linear speed/radius:  angular speed = 20*pi/5 = 4*pi radians per second.  There are 2*pi radians in one revolution so they are making 2 revolutions per second.

 

4.  Given the above three solutions you should be able to do the fourth one.

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