a^=1 ('a' the power of zero, is equals to 1) by what substitution you get the answer ? give clear response?

Answer 1

Anything^0 = 1

well maybe
Anything^x = 1
x * log Anything = log 1
x = log 1/log anything
but log 1 = 0
x = 0

Answer 2

using the properties of exponents,
a^5/a^5 = a^(5-5) = a^0 = 1
works for any power, not just 5.