Tony and Maria are two star-crossed lovers trying to get on a committee of 4 people. If there are 10 people eligible for this committee, how many ways can exactly one of Tony and Maria be selected for the committee?

How to do this , and can some one explain

The fraction of defective integrated circuits produced in a photolithography process is being studied. a random sample of 300 circuits is tested, revealing 17 defectives. (a) calculate a 95% two-sided confidence interval on the fraction of defective circuits produced by this particular tool. round the answers to 4 decimal places. less-than-or-equal-to p less-than-or-equal-to (b) calculate a 95% upper confidence bound on the fraction of defective circuits. round the answer to 4 decimal places. p less-than-or-equal-to

David leaves his house to go to school. he walks 200 meters west and 300 meters north. how far is david from his original starting point?