Which function has the values f(4)=-15 and f(7)=57 A) f(x)=14x-71
B) f(x)=24x-1361
C) f(x)=24x=360
D) f(x)=24x-111

It says in the questions that it is 6.5?

So don't take my word i'm not exactly a mathematical person but i would assume a. because while selling the soap every month you increase in sells so you would by 11 percent. the you would get the factor 0.89 which if i had to guess would be the monthly profit over 11 probably wrong tho