I need help one this one

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

The annual snowfall in a town has a mean of 38 inches and a standard deviation of 10 inches. last year there were 63 inches of snow. find the number of standard deviations from the mean that is, rounded to two decimal places. 0.44 standard deviations below the mean 2.50 standard deviations below the mean 0.44 standard deviations above the mean 2.50 standard deviations above the mean

In the sixth grade 13 out of 20 students have a dog if there are 152 sixth grade students how many of them have a dog