Answer:

Step-by-step explanation:

9^-2 = 1/81 or 0.0123
When there is a negative in front of the exponent it makes a fraction. It is usually just 1/the number it equals if it were positive.
Answer:
The second and fourth option
Step-by-step explanation:
In order for two lines to be perpendicular they must intercept each other and their slope must be the opposite inverse; ex:
the negative inverse is 4 (multiplying by -1 and flipping the fraction)
5/10 and 2/10 beacuse tenth is the bottom number