What is the frequency of a pressure wave of wavelength 2.5 m that is traveling at 1400 m/s?

Achemistry student needs of 40ml diethylamine for an experiment. by consulting the crc handbook of chemistry and physics, the student discovers that the density of diethylamine is 0.7 . calculate the mass of diethylamine the student should weigh out. round your answer to significant digits.

Given the position vector of the particle r(t)=(t+1)i+(t^2−1)j+2t k, find the particle's velocity and acceleration vectors at t=1

Using a pedometer, you walk 3000 steps in 20 minutes, so your speed is 150 steps/min. each of your steps is 0.7 m long. what is your speed? 150 steps/min=/s=/h