Using the periodic table, choose the more reactive nonmetal.

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bromine is more reactive non-metal.

Explanation:

Both the elements have to gain 1 electron but the size of bromine is less than the size of astatine. And therefore, the tendency of accepting an electron by bromine is more than the tendency of astatine. Hence, bromine is more reactive non-metal.

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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