Please help me i've been stuck for over an hour... A hockey puck travels a distance of 11 m [N] in 0.55 s and is then hit by another player and travels a distance of 26 m [W 42° N] in 1.2 s. Calculate the average velocity of the puck.

A175 g lump of molten lead at its melting point (327 c) is placed into 55.0 g of water at 20.0 c. the specific heat of lead is 130.j/kg c and the hf of lead is 20,400 j/kg. when the lead and the water have reached equilibrium, what is the temperature of the mixture?

If it takes a planet 2.8 x 10^8 s to orbit a star with a mass of 6.2 x 10^30 kg what is the average distance between the planet and the star

What are similarities and differences of reflection, refraction, diffraction and absorption?