What variable is used to represent SLOPE?

Find the magnitude, correct to two decimal places, made by each of the following with positive direction of the x axis a) y= x the answer is 45° but i don’t know how

Madeline takes her family on a boat ride. going through york canal, she drives 6 miles in 10 minutes. later on as she crosses stover lake, she drives 30 minutes at the same average speed. which statement about the distances is true?

The plant were you work has a cylindrical oil tank that is 2.5 feet across on the inside and 10 feet high. the depth of the oil in the tank is 2 feet. about how many gallons of oil are in the tank?