HELP WILL GIVE BRAINLIEST!! AND 75 POINTS

Evaluate the dot product of (3,-1) and (1,5)

Find the difference (8ab+a+2) - (3ab+6)

Assume that the weights of quarters are normally distributed with a mean of 5.67 g and a standard deviation 0.070 g. a vending machine will only accept coins weighing between 5.48 g and 5.82 g. what percentage of legal quarters will be rejected? round your answer to two decimal places.