Which is capable of housing astronauts while they conduct research?

a rover
a satellite
a space station
a space observatory

Astudent is looking through a microscope at some cells of an onion root tip. many of these cells are undergoing division since the root tip grows quickly and requires more cells. which cell most recently underwent metaphase? w x y z

Look at the photo of the leaf, which term best describes this leaf ? a-simple.b-parallel.c-lobed.d-tooth.

The law of thermodynamics states that energy can't be created or destroyed. to natural sources of energy on earth are the