Easy
remember
(x^m)(x^n)=x^(m+n)
basically add exponens when the base is same
(13^-11)(13^16)(13^-3)(13^4)(13^-5)=
13^(-11+16-3+4-5)=
13^(5-4)=
13^1=13
C is the only one greater than 12.5 i think so
also b and d
hey its -100 percent. the negative to show decrease.
This is how to solve this
A)Theorem. every theorem can be proved.