A DVD is approximately 13 centimeters in diameter The drive

A DVD is approximately 13 centimeters in diameter. The drive motor of the DVD player rotates precisely between 300 and 400 revolutions per minute, depending on what track is being read. (a) Find an interval for the angular speed of a DVD as it rotates. (Enter your answer using interval notation.) (b) Find an interval for the linear speed of a point on the outermost track as the DVD rotates. (Enter your answer using interval notation.)

Solution

DVD\'s circumference = d = 13

A)
Since one revolution is 2 radians, it will make between 2*300 = 600 and 2*400 = 800 radians/minute
So the answer is [600, 800] radians/minute
please use the square brackets

B)
Since the DVD\'s circumference is 13, it will travel between 13*300 = 3900 and 13*400 =5200
So the answer is [3900, 5200] centimeters/minute