What's phase changes mean? I can't find it

A child is playing on a trampoline jumping up and down. She is very skillful in playing on the trampoline, and at every bounce she reaches the same height always.

Cassie lives two miles away from school. Which mode of transport could benefit her health? A. taking a bus to school B. riding a bicycle to school C. being driven to school D. taking a cab to school

Before beginning an experiment, Mrs. Wilson warns her science class not to drop the bar magnets on the floor. What is the most likely reason for Mrs. Wilson's warning?

The Michelson-Morley experiment showed that the speed of light varies depending on the direction of the ether wind. True False

What is the energy in electron-volts (eV) of a photon of green light that has a wavelength of 520 nm? (1.0 m = 1.0 * 10^-9m) 3.8 * 10^-19eV 3.4 * 10^-40eV 2.4eV 2.2 * 10^-21eV

If the Coast Guard warns of a giant wave of water approaching the shore as a result of a major earthquake, they are warning of a. an aftershock. b. liquefaction. c. a tsunami. d. landslides.

What is the total number of atoms in the following formula? CaBr2 4 3 2 1

Object A with a mass of 500 kilograms hits stationary object B with a mass of 920 kilograms. If the collision is elastic, what happens after the collision? A) Both object A and object B move forward but with different velocities.

A young man walks daily through a gridded city section to visit his girlfriend, who lives m blocks East and nblocks North of where the young man resides.

Aliens from planet Moby have three alleles for skin color: R (red) W (white) and B (Blue). If all of these alleles are codominant and aliens on planet moby can only inherit two alleles for a gene, what are the six possible genotypes for skin color