can you please check my answers

Question

evaluate (-5a)^2 and -5a^2 when a =5
625 for both
1-12.64=-11.64
(-14)/(-7)=2
using multiplying by 1to find an expression equvialnt to 18/19 with a denomanator of 171z?dont simplfy type a fraction
one day the temperture dropped from -4 degree f to -12 degerees f how much did it drop? 8 degrees
18x+18y+180 factor x+y+18=10

Answer 1

The first 4 are correct.

I'm not sure what you are asking for "multiplying by 1." Anything multiplied by one remains the same.

Degrees are correct.

18x + 18y + 180 = 18(x + y + 10)