Answer for 7: C
Answer for 9: A
Step-by-step explanation for 7:
Because the variable is an exponent, we know there are no real numbers which cannot be placed in the exponent. Therefore, the domain is all real numbers.
Step-by-step explanation for 9:
Test a few values for x. Notice as the x value gets higher, the y value gets exponentially higher. Notice as the x value gets lower, the y value approaches 0, but no value of x will have y equal to or less than 0. Therefor, the asymptote, or line that cannot be crossed is 0 - making A the correct solution.