The minute hand on a clock is 10 mm long and the hour hand is 7 mm long. How fast is the distance between the tips of the hands changing at 6:45?

Please show all work and explain. Thanks.

a minute hand on a watch is 8 cm long and the hour hand is 4 cm long, how fast is the distance between the tips of the hands changing at 2-o-clock (in cm/sec)

The minute hand on a watch is 8 mm long and the hour hand is 5 mm long. How fast is the distance between the tips of the hands changing at one o'clock? (Round your answer to one decimal place.)

The minute hand of a steeple clock is 4 feet long and the hour hand is 3 feet long. How fast is the distance between the tips of the hands changing at 3 o'clock? (Hints: Use the law of cosines to compute the distance between the tips of the hands. The rates of change of the angle between the hands can be computed since the rate of each hand (radians per minute) is known.