1 (a) Stefan had an annual income of $21 500 in 2018. His annual income increased to $22 790 in 2019. Calculate the percentage increase. (b) Stefan invests $1260 in a bank. The bank pays simple interest at a rate of 2.5% per year. Calculate the amount Stefan has in the bank at the end of 3 years. (c) Stefan changes 4300 Indian Rupees (INR) into dollars ($). The exchange rate is $1 = 67.8 INR. Work out how much he receives. Give your answer correct to the nearest dollar.