How is chemical energy related to chemical change

Which statement justifies that phosphine (ph3) is a polar molecule?

If i can still dissolve more sugar into the solution at a certain temperature what would i call that solution

Three cards with holes are arranged in a straight line. a light is shined through the first card’s hole and travels through all three cards. what does this tell you about light rays? a) that light is reflected b) that light is refractive c) that light travels in a straight line d) that light does not travel in a straight line