A sum of $1,000 is deposited in three accounts, earning 4%, 6% and 8% simple interest. After one year, the total interest earned is $70.
a) Set up the system of two equations in three variables, and employ your calculator to rewrite this system in reduced row echelon format
b) If $600 is deposited at 8%, how much was deposited at 4%?
c) Determine the maxiumum amount that can be deposited at 8% in order for the initial conditions to remain true?