Please answer the following questions clearly so I can read them, indicate the formula you are using, and please draw a diagram according to your results? Thank you.

1. To determine the effect of advertising in the Yellow Pages, a researcher took a sample of 37 retail stores that did not advertise in the Yellow Pages last year (pop1) but did so this year (pop2).The annual sales of the stores were recorded and the mean of the sample differences was -$4.92 and the standard deviation of the sample differences was $31.95.Assume matched pairs.Using a 1% level of significance, can we conclude that advertising in the Yellow Pages increased sales?
2. An OSHA agent wanted to determine if efforts to promote safety have been successful. By checking the records of 250 (n1) workers, he found that 30 (x1) of them suffered either minor or major injuries that year. A random sample of 400 (n2)workers last year revealed that 80 (x2) suffered some form of injury. Can the statistician infer at the 5% significance level that efforts to promote safety have been successful?
3. If we reject the null hypothesis, we conclude that:

a. there is enough statistical evidence to infer that the alternative hypothesis is true.

b.there is not enough statistical evidence to infer that the alternative hypothesis is true.

c.there is enough statistical evidence to infer that the null hypothesis is true.

d.there is not enough statistical evidence to infer that the null hypothesis is true.