What is a hybrid? PLEASE HELP

Genetic disorders can result when sister chromatids fail to seperate properly. during what phase is this problem most likely to occur?

Why is it impossible for exponential growth to continue forever?

Paleontologists have found plant fossils deep within the layers of the north polar region. these leaf fossils have been labeled as to the rock layers they were found in, with the lower numbers being layers close to the earth's surface and higher numbers representing deeper layers. according to the numbers of these four leaf fossils, what might you infer?