A A student shakes the end of
a rope
with
frequency of 1.5 Hz, causing waves with a
wavelength of 0.8 m to travel along the rope.
What is the velocity of the waves?

The speed of light in a material is 0.50 c. what is the critical angle of a light ray at the interface between the material and a vacuum?

The air that we breath is made mostly of which gaseous molecule

The number of passengers who arrive at the platform of a subway station for the 10 am train is a random variable with a mean of 120 and a variance of 16. find the lower bound of the probability that there will be between 100 and 140 passengers (round off to second decimal place).