Can any one help?

Solve the following equations:

The scale for a map is 20 miles = 1/2 inch. the distance between two towns on the map is 3 3/4 inches. what is the actual distance between these towns? 150 miles 38 miles 75 miles 135 miles

Rockwell hardness of pins of a certain type is known to have a mean value of 50 and a standard deviation of 1.1. (round your answers to four decimal places.) (a) if the distribution is normal, what is the probability that the sample mean hardness for a random sample of 8 pins is at least 51?

Write numerical coefficient of y² in the expression 2x² - 15xy – 7y²