3. In order to save money to buy a car, Renee decides to start an annuity. She deposits $500 the first month and increases the amount of each monthly deposit by $50 for a period of 15 months. The value of the last deposit Renee makes is A. $1200 C. $12750 B. $1900 D. $13125 4. In the geometric series Ss = -19680, if the common ratio of the series is 3, which of the following equations can be used to determine the value of the first term? 9840 9840 A. 38 -1 C. 37 39360 39360 8 B. 3 - D