Answer:
D
Explanation:
The decrease in potential energy is equal to the increase in kinetic energy.
mgh
250 x 9.8 x 30
=73, 500
The formula for the mass that remains:

m₀ - the initial mass, t - time, T - the half-life

The answer is c. 1.25 g.
Answer:
400cm^2
Explanation:
sides are 20cm long Area for a square is a squared
since all the lides are of equal length you can just choose one side.
20squared is 400
20 x 20 = 400cm squared
Hope this helps :)
"The" (and any subsequent words) was ignored because we limit queries to 32 words.