Can someone please help me ASAP!

Determine the fraction of total interest owed. after the fourth month of a 12-month loan: the numerator is: {(n + ) + (n + ) + (n + ) + (n + )} = , and the denominator is: {(n) + (n + 1) + + (n + )} = . therefore, the fraction is numerator/denominator (to the nearest tenth) =

What is the effect on the graph of the function f(x)=x when f(x) is replaced with -f(x)+4

Mat bought a phone for $100. he has to pay $30 per mouth. if he has paid $640 in total, how many mouth has he had the phone?