Hello, I have a physics test on Wednesday and am currently studying for it. Can anyone help me? Even if I only have one answer, it helps. How are things going?

1. The tip of the large hand of a wristwatch is 12 mm from the axis. Calculate the circumferential speed of the hand tip in mm/min and cm/h.
2. The cutting speed of a grinding wheel with a diameter of 180 mm must not exceed 20 m/s. Calculate the rotational frequency in Hz and rpm.
3. The rear wheel of a motorcycle has an angular velocity of 3500 rpm. The motorcycle is traveling at 72 km/h. Calculate the diameter of the wheel.
4. The wheel of a car travels at a speed v. A point on the circumference of the wheel also has a circumferential speed v if the wheel rolls without slipping. Prove the following statements:

a) The point of the wheel that is just touching the road is at rest relative to the road.

b) The highest point of the wheel has twice the speed compared to the road.