Answer:
15
Step-by-step explanation:
The formula for factoring a sum of cubes is:

We have a=3f and b=5g here.
So a*b in this case is 3f*5g=15fg.
The ? is 15.
Answer:
milligram would be 3.2e+7 or if not 3.2
one correct equation would be 2x=28 to depict the amount of money earned and then you would do 28/3 to find out the amount of money they each have after splitting the money they earned.
For the first one...
1,15
2,30
3,20
and for the second one is the same as the first one.
EXTRA CREDIT:
Week one increases by 15, week two increases by 15 but week three decreases by 15. The total miles ran would be 15 miles
15+15=30 30-15=15 miles
More information is required to answer the question correctly.