Answer this question and explain if you can

Which equation represents a proportional relationship that has a constant of proportionality equal to 1/5

After the seventh month of a 12-month loan: the numerator is: {(n + 11) + (n + 10) + (n + 9) + (n + 8) + (n + 7) + (n + 6) + (n + 5)} = , and the denominator is: {(n) + (n + 1) + + (n + 11)} = . therefore, the fraction is numerator/denominator (to the nearest tenth) = %

Express the following as a function of a single angle. cos(60) cos(-20) - sin(60) sin(-20)