In 2004 the company reported that the national college freshman-to-sophomore retention rate held steady at 7496 over the previous four years. consider random samples of 400 freshmen who took the act. use the 68—95—99.7 rule to describe the sampling distribution model for the percentage of those students we expect to return to that school for their sophomore years. do you think the appropriate conditions are met?

Step-by-step explanation:

Try something like this but in the notation that you're using.

1. | ~( (~Q ->~R) v (R & ~Q) ) Assume

2. | |  ~(~Q ->~R) Assume

3. | | |  ~(R & ~Q) Assume

4. | | |  ~R v Q    3, De Morgan

5. | | |  ~Q -> ~R 4 Material implication

6. | | |  # 2, 5 Contradiction

7. | | R & ~Q 3-6 indirect Proof

8. | ~(~Q ->~R) ->   (R & ~Q ) 2-7 Cond. Proof

9. | (~Q ->~R) v (R & ~Q) 8 Material implication

10 | # 1,9 Contradiction    

11.  (~Q ->~R) v (R & ~Q) 1-10 Indirect proof