How much interest is earned on a principal of $2.58 invested at an interest rate of 5% for four years?

Step-by-step explanation:

The formula for simple interest is

prt = I, where p is the initial investment, r is the interest rate in decimal form, t is the time it's invested for, and I is the interest earned. We multiply the p, the r, and the t together to get I. For us that looks like this:

(2.58)(.05)(4) = I and

I = .516 or 52 cents.