Why do black things stay black in sunlight

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.

Can anyone plz answer any of these. even if its one it will

Tsunamis are fast-moving waves often generated by underwater earthquakes. in the deep ocean their amplitude is barely noticeable, but upon reaching shore they can rise to an astonishing height of a six-story building. one tsunami generated off the aleutian islands in alaska, had a wavelength of 897km and traveled a distance of 3280km in 4.18h. (a) what was the speed (in m/s) of the wave? find the waves (b) frequency and (c) period.