Derive the equation of the parabola with a focus at (0, −4) and a directrix of y = 4.

a.) f(x) = −16x^2
b.) f(x) = 16x^2
c.) f(x) = −1/16 x^2
d.) f(x) = 1/16 x^2

Mindy bought 5/8 pound of almonds and a 3/4 pound of walnuts. which pair of fraction cannot be used to find how many pounds of nuts she bought in all.

The volume of a cube is 8 in to the 3rd power. how long is each side?

Hii1977 cleaner shrimp are a species of shrimp that clean parasites from other organisms. fish allow the shrimp to eat the parasites in their mouth. the shrimp get a source of nutrition. the relationship between the shrimp and the fish is this association indicates that for the smaill aneser arecommensal, mutualistic, or parasitic for the begger one the anser are the shrimp and fish benefit each other , the shrimp harm the fish, or the fish do not benetit from the shrimp