I figured out the first question, the second one in lost on.

Factor both of the equations, numerator and denominator

Cancel the like factors *excuse the zero im just showing you*

Combine frunctions

x-9=0
x+7=0
Restrictions are 9 and -7
Answer: 2-17
Step-by-step explanation:
I worked it out, i'm pretty sure its the answer, let me know if its wrong.
Answer: The required time is 0.743.
Step-by-step explanation:
Since we have given that

We need to find the time above which is 68% of the cameras have to be reset.
So, exponential distribution would be

So, it becomes,

Hence, the required time is 0.743.