Tonys son, Mark is 12 years old and Tony expects him to start college in 6 years. Tuition costs $20,000 today, increasing at an annual rate of 7%. Tony wants to earn 10% annually on his investments. If he makes an initial investment one year from now, and annual additions at the end of each year until Mark starts college, what is the size of the annual (level) investments he must make to fund 4 years of Marks college education?

a. $10,268.08

b. $12,192.77

c. $11,294.89

d. $14,935.39