Ultraviolet light causes production of vitamin D3 in the cells of the .
A. dermis
B. hypodermis
C. epidermis
D. ultraviolet light causes vitamin D3 production in all of these areas

Why are scientists concerned about the depletion of the ozone levels in the stratosphere?

What type of reaction is photosynthesis

1. you serve a volleyball with a mass of 2.1 kg. the ball leaves your hand with a speed of 30 m/s. the ball has energy. calculate it. 2. a baby carriage is sitting at the top of a hill that is 21 m high. the carriage with the baby weighs 12 n. the carriage has energy. calculate it. 3. a car is traveling with a velocity of 40 m/s and has a mass of 1120 kg. the car has . calculate it.