Answer:
because they devlop our organs
Answer:
Fossil fuels.
Explanation:
A fossil fuel is a fuel obtained from nature such as crude oil, coal, wood etc. The burning of fossil fuels releases tremendous amounts of carbon IV oxide into the environment causing a myraid of environmental problems paramount among them is global warming with its attendant consequences.
Answer:
3 years
Explanation:
Given data:
Initial amount of sample = 160 Kg
Amount left after 12 years = 10 Kg
Half life = ?
Solution:
at time zero = 160 Kg
1st half life = 160/2 = 80 kg
2nd half life = 80/2 = 40 kg
3rd half life = 40 / 2 = 20 kg
4th half life = 20 / 2 = 10 kg
Half life:
HL = elapsed time / half life
12 years / 4 = 3 years
The potential energy ..
1- when a rubber band is stretche and waiting to be released
2- an acorn hanging from a oak tree
3- a pice of celery
