You can hear someone around the corner before you can see them due to reflection, diffraction, refraction, or absorption?

What is a possible result of higher air temperature caused by global warming

For the car in the picture ,in which direction is the normal force? -into the screen -down -out of the screen -up

Agraduated cylinder contains 63.0 ml of water. a piece of gold, which has a density of 19.3 g/ cm3, is added to the water and the volume goes up to 64.5 ml. calculate the mass in grams of the gold that was added to the water. explain how you got your answer.