HELP PLEASE!! 4. When Earth is closest to the sun, the Northern Hemisphere is in
winter. (20 points)
A. Why is this true? (10 points)
The North Pole of the Earth's axis is tilted away from the sun which
causes it to be winter in the northern hemisphere.
B. Given the effects of precession, will this still be the case in
13,000 years? Explain your answer. (10 points)

Positrons are spontaneously emitted from the nuclei of

Abag of potato chips contains 2.00 l of air when it is sealed at sea level at a pressure of 1.00 atm and a temperature of 20.0 deg c. what will be the volume of the air in the bag if you take it with you, still sealed, to the mountains where the temperature is 7.00 deg c and atmospheric pressure is 70.0 kpa? assume that the bag behaves like a balloon and that the air in the bag is in thermal equilibrium with the outside air.

This is the number of complete movements of a wave per second.