This isn’t physics but is science and I couldn’t find science so anyways here’s the question How are matter and energy conserved in ecosystem?

How does the image distance (di) of a convex lens compare with the image distance of a concave lens? a. the image distance of the convex lens is positive, and that of the concave lens is negative. b. both are negative for a virtual image. c. both are positive for a virtual image d. the image distance of the convex lens is negative, and that of the concave lens is positive.

Which is special about a dc circuit ? a. it has both series and parallel components b. it has only series or only parallel components c. charge moves in a single direction d. charge moves back and forth quickly

An isotope undergoes radioactive decay by emitting radiation that has a –1 charge. what other characteristic does the radiation have?