For convection to occur,
a. dark objects are required to absorb energy.
b. substances must be in contact with each other.
c. particles must be able to flow within a substance.
d. heat must transfer from an area of less energy to more energy.

An equinox occurs when a. neither end of earth's axis is tilted toward or away from the sun. b. the north end of earth's axis is tilted away from the sun. c. the north end of earth's axis is tilted toward the sun. d. earth's axis is parallel to the sun's rays. select the best answer from the choices provided a b c d

When does your body conduct current more readily?

Suppose you have three polarizing filters, with the second at an angle of 42∘ to the first and the third at an angle of 90∘ to the first. by what perfect will the original intensity of unpolarized light be reduced to after passing through all three filters?