Jones bought a car for GH 6,800.00. He later put it up for sale at GH¢8,800.00. He agreed to sell it to Ruby under the following hire purchase terms: An initial payment of 20% of the price and the balance paid at 15% simple interest per annum in twelve monthly equal instalments. Calculate: a) the amount paid every month; b) the total amount Ruby paid for the car; c) the percentage profit Jones made on the cost price of the car.