half life, for my physics but pretty sure it involves maths. you don’t have to do them all i’m just confused how to work it out.

The frequency of the fundamental of the guitar string is 320 hz. at what speed v do waves move along that string?

A( developed during the process of technology design

The friction of the water on a boat produces an acceleration of -10. m/s2. if the boat is traveling at 30. m/s and the motor is shut off, how long it take the boat to slow down to 5.0 m/s?