What is the movement of water across a membrane from an area of high concentration to an area of low concentration 

Osmosis

Explanation:

The movement of water across a membrane from an area of high concentration to that of low concentration is defined as osmosis.

Osmosis is very important in all living cells because it is one of key mechanism for transporting materials between and within cells.

The membrane most times is selectively permeable in nature and it allows for a regulated movement of materials from one region to another.

for step 7 table c on the lab "newtons law of action"   the average time it took the car to travel .25 meters   was 1.92 seconds.

the average time it took the car to travel 0.50 meters was 2.61 seconds

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