Mr. Kent teaches 7 classes that are each 50 minutes long. he Lao has a 30-minute lunch break. how much time does mr. kent spend teaching class and at lunch?

The weight of an object in a particular scale is 175.2 lbs. the measured weight may vary from the actual weight by at most 0.1 lbs. what is the range of actual weights of the object

(! ) three cylinders have a height of 8 cm. cylinder 1 has a radius of 1 cm. cylinder 2 has a radius of 2 cm. cylinder 3 has a radius of 3 cm. find the volume of each cylinder

Donald has x twenty-dollar bills and 11 ten-dollar bill. how much money does donald have? write your answer as an expression.