Miguel wanted to ensure that she had $75,000 for her child's university education. As soon as her child was born, she started saving $1,200 every 6 months in an investment fund. If she achieved her investment target on her child's 19th birthday, and she made no deposit on the child's 19th birthday, calculate the following:

a. The nominal interest rate for the investment, compounded quarterly.

%

Round to two decimal places.

b. Calculate the effective interest rate for this investment.

% Round to two decimal places.