Help! Will give you medal and become a fan! Need step by step instructions.

The deposits Ginny makes at her bank each month form an arithmetic sequence. The deposit for month 3 is $150, and the deposit for month 5 is $180. Answer the questions below and show all work.

1. What is the common difference for the deposits made each month?
2. Write an explicit formula for this arithmetic sequence.
3. What is the amount of Ginny’s deposit in the 12th month?
4. At what month will Ginny first make a deposit that is at least $500? (4 points)

Question

Help! Will give you medal and become a fan! Need step by step instructions. 

The deposits Ginny makes at her bank each month form an arithmetic sequence. The deposit for month 3 is $150, and the deposit for month 5 is $180. Answer the questions below and show all work. 

1. What is the common difference for the deposits made each month? 
2. Write an explicit formula for this arithmetic sequence. 
3. What is the amount of Ginny’s deposit in the 12th month? 
4. At what month will Ginny first make a deposit that is at least $500?  (4 points)