Why are some motors painted black?
a)
black is a standard color code for motors.
b)
this prevents loss of heat from the motor.
c)
the motor is hotter than the surroundings and emits heat.
d)
the motor runs on heat energy and the black color absorbs heat from its surroundings.

What are the doorways into and out of cells, attached to the membrane, and built in the rough er.

Which gas found in the earth's atmosphere greatly impacts the daily range of temperature on earth. a) oxygen b) hydrogen c) nitrogen d) water vapor

Amino acids contain the elements carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur. of the 20 amino acids found in humans, 11 are called "nonessential" because they can be manufactured by the body when needed. which elements in these 11 amino acids are commonly obtained from the metabolism of sugar molecules?