What does a positive (+) acceleration tell you about an object's motion?

It tells you that the object's velocity is increasing.

cell differentiation  is how generic embryonic  cells  become specialized  cells. this occurs  through a process called gene expression. gene expression is the specific combination of genes that are turned on or off (expressed or repressed), and this is what dictates how a  cell  functions.

explanation:

c because the action was the roller coaster reaches bottom of hill (action) reaction would be blood tends to drain away from head

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