FILL IN THE BLANK: Paleontologists study ancient organisms. Over millions of years, sediment hardens into rock and preserves the remains of living
things. A
is the impression that an organism or part of
an organism leaves in rock.

Quickly! brainliest if two people answer! 1. the blood has red blood cells, white blood cells and platelets. red blood cells carry oxygen to other cells in the body. cells need oxygen to live. white blood cells destroy certain germs. they protect our bodies from disease. which question is answered in this paragraph? (a) what is the role of blood vessels? (b) what type of cells are attached to bones? (c) what type of blood cell to clot your blood? (d) what are the different types of blood cells? 2. which sentence from the section "stem cells" best explains the role of stem cells? (a) when one kind of cell stops working, stem cells can . (b) they can turn into that cell and take its place. (c) scientists are studying new ways to use stem cells. (d) these cells can people heal faster. 3. read the selection from the section "nerve cells." nerve cells send messages to the rest of our bodies. these messages move between the brain, spinal cord and various organs. nerve cells are also called neurons. fill in the blank. a "neuron" is a (a) cell that moves information from the brain to other parts of the body (b) stem cell that has both an axon and a dendrite (c) cell that controls the fingers of a body (d) cell that makes up the spinal cord 4. some muscles in our body move without us telling them to. these are called involuntary muscles. some examples are the cardiac muscle cells inside the heart. these cells the heart relax and fill with blood. what is the best definition of "involuntary" based on the context clues? (a) something that happens on its own (b) trying hard to do something (c) something moving back and forth (d) easily moved

Fill in the blanks for the following statements: the rms speed of the molecules in a sample of h2 gas at 300 k will be times larger than the rms speed of o2 molecules at the same temperature, and the ratio µrms (h2) / µrms (o2) with increasing temperature. a not enough information is given to answer this question b sixteen, will not change c four, will not change d four, will increase e sixteen, will decrease

Compounds a and b react to form compounds c and d according to the equation: aa + bb → cc + dd. under which conditions will the rate law be given by the equation: rate = k[a]a[b]b? a. the reaction takes place in one step. b. the reaction is endothermic. c. the reaction is exothermic. d. the reaction involves more than one step.