The sleep stage at which muscles begin to contract and relax is . A. Stage 1b. Stage 2c. Stage 3d. Stage 4 please select the best answer from the choices providedabcd.

Either stage 3 or stage 2

Explanation:

i read it before it cant be stage 4 because your muscles have already been contracted and relaxed they don't begin

if you break down the data from the global footprint network, china exerts far more pressure on its ecosystems per capita than america in terms of crops, grazing, foresting, and fishing. but where america blows everybody out of the water is carbon emissions per capita