7. A person makes a $1200 investment. For each description of how the investment is increasing/decreasing in value, write a formula for the value of the investment after t years. (a) Every year, the investment increases by 12% of the original value. (b) The investment grows at a continuous rate of 6% each year. (c) The investment loses 5% of its value each year. (d) The investment triples in value every 15 years. (e) The investment loses $10 in value every month. (f) The value increases by 0.8% each month. (g) The value grows by 5% each year for 5 years, then decreases at a continuous rate of 2% per year for three years, then continues growing again at its original growth rate