Answer:
1. The correct option is d.
2. The correct option is c.
3. The correct option is a.
Explanation:
1.
The given expression is

Using property of exponent the given expression can be written as
![[\because a^(-n)=(1)/(a^n)]](https://img.qammunity.org/2018/formulas/mathematics/high-school/ky1wjuuhdi36r9drgbwslu92xc4g6ng20n.png)
Therefore, the correct option is d.
2.
The given expression is

Using property of exponent the given expression can be written as
![[\because a^(-n)=(1)/(a^n)]](https://img.qammunity.org/2018/formulas/mathematics/high-school/ky1wjuuhdi36r9drgbwslu92xc4g6ng20n.png)
Put a=-5


Therefore option c is correct.
3.
The given expression is

Using property of exponent the given expression can be written as

Put m=2 and n=-24.



Therefore option a is correct.