How do astronomers measure the amount of dark matter in the universe

If i was a potato > .< then wat would u be

The sun a. will become a red giant within two to three million years b. is in its main sequence, which willlast thousands of years c. is in its main sequence, which will last billions of years. d. will explode as a supernova after its main sequence

Hurry: the angle measures associated with which set of ordered pairs share the same reference angle? (-square-root 3/2, 1/2) , (-1/2, -square-root 3/2) (1/2, -square-root 3/2) , (-square-root 3/2, 1/2) (-1/2, -square-root 3/2), (1/2, square-root 3/2) (square-root 3/2, 1/2) , (1/2, square-root 3/2)