Please solve the following maths correctly asap

1. The college bookstore tells prospective students that the average cost of all textbooks is $52 with a standard deviation of $4.50. A group of smart statistics students thinks that the average cost is higher. In order to test the bookstore's claim against their alternative, the students will select a random sample of size 100. Assume that the mean from their random sample is $52.80. Perform a hypothesis test at the 5% level of significance and using the critical value approach state your decision.

2. A certain chemical pollutant in the Genesee River has been constant for several years with mean = 34 ppm (parts per million) and population standard deviation = 8 ppm. The population standard deviation is skewed to the left. A group of factory representatives whose companies discharge liquids into the river is now claiming that they have lowered the average with improved filtration devices. A group of environmentalists will test to see if this is true at the 4% level of significance. Assume that their sample of size 50 gives a mean of 32.5 ppm. Perform a hypothesis test at the 4% level of significance and using the critical value approach state your decision.