100 points!! plz answer im indanger of faling

If f(x)=x^3 and g(x)=2x+7 when g(x)=-5

The table shows the webster family’s monthly expenses for the first three months of the year. they are $2,687.44, $2,613.09, and $2,808.64. what is the average monthly expenditure for all expenses?

What is the least common factor of 6 and 8