White light shines on a piece of paper whose atoms are capable of absorbing orange, indigo, violet, yellow, red, blue, and green. what color is the paper?
black
white
brown
gray

answer: a) black

explanation:

what my friend meerkat18 was trying to explain is that a paper that is colored black will absorb all the given colors. a paper that is white or green will just reflect the given colors.

answer: the blood-brain barrier is a layer of specialized membranes and cell processes designed to keep undesirable substances from passing from the bloodstream into the precious tissues of the brain. while the blood-brain barrier does keep most bad things out of the central nervous system, it is not impermeable.

explanation:

the second type of galaxy is called a barred spiral, which has a thing called a bar straddling the nucleus