I'll go through it backwards: 12^7 times 12^-5 You subtract the -5 from 7 in the exponents to get 12^2. 12^2 divided by 12^2 is 1.
(12^2)^3 works out to 12^6 because you multiply the exponents when its a power raised by a power. Then you subtract the 4 from the 6 (or add -4 +6) to get 12^2.
That means 12 squared, same as 12 times 12
That's 144.
If you have to multiply the two parts together, It's 144 times 1.
Answer: It would be 1/2 divided by 5. In other words 1/2 times 1/5. That equals 1/10. Each plant would get 1/10 of a gallon each. To check you would multiply 1/10 times 5.<em> </em><em>That equals</em><em> </em><u><em>1/2</em></u>