Answer:
A = -10
Step-by-step explanation:
Combine multiplied terms into a single fraction find common denominator etc etc.
Answer:
The answer is "120".
Step-by-step explanation:
Given values:

differentiate the above value:




Note that all of these choices but the last have 1-number responses. The last choice involves collecting data: the ages of the concert attendees. So only the last pertains to statistics.