True or false: a sphere is made up of two flat surfaces and one curved surface.

Which is the equation of an ellipse with directrices at x = ±4 and foci at (2, 0) and (−2, 0)?

How to choose the sign of the radical in the denominator of the formula for the distance from a point to a line.

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