Common feature among class reptile, osteicthyes and aves is the possessing of? ps. i need the answer asap

What are some things that limit population growth?

Suppose you could go back in time to interview henri becquerel on the day he discovered radioactivity. from his perspective, write an account of the discovery.

Ivan is looking at a cross section of a stem taken from a vascular plant. he sees two different types of vascular tissue: the xylem, which is closer to the center of the stem, and the phloem, located around the xylem, closer to the outside of the stem. how do these two structures work together in a living plant?