Acids react with metals to produce a. water and a salt b. hydrogen gas c. a base

Hydrogen gas. The effect bubbles up and causes a gas. Most metal react to acid but some do not.

3 1/4 %

explanation:

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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