trigonometry probability problem, please show works instead of only answers

Question

Football Plays Problem Backbay Polytechnic Institute's quarterback selects pass plays and run plays randomly. His probability of selecting'JT" pass on first down is 0.4. If he selects a pass on first down, his probability of selecting another pass on second down is 0.3. Otherwise, his prob ability o f passing on second down is 0.8. What is his probability of passing in each situation?

1. First down and second down?
2. First down but not second down?
3. Second down but not first down?
4. Neither first down nor second down?

please show works instead of only answers

Answer 1

------>P 0.4------->P0.3---->PP= .4x.3 = 0.12

------>R0.7---->PR = .4 x .7= 0.28

----->R. 0.6------>P0.8 ---->RP = .6 x .8 = 0.48

------>R0.2 ----> RR = .6 x ,2 = 0.12. Notice the ending probabilities sum to 1.0