Which of the following best describes the use of a renewable resource? (2 points) a. most power plants burn fossil fuels to generate electricity for use in homes, offices, and other buildings. b. propane is a product you might use to barbecue; it comes from natural gas and processing oil. c. there are areas in california that use the heat from deep in the earth to generate electricity. d. we use gasoline to power our cars to get to work and school each day.

Atrain departs from its station at a constant acceleration of 5 m/s. what is the speed of the train at the end of 20s?

Consider an ordinary, helium-filled party balloon with a volume of 2.2 ft3. the lifting force on the balloon due to the outside air is the net resultant of the pressure distribution exerted on the exterior surface of the balloon. using this fact, we can derive archimedes’ principle, namely that the upward force on the balloon is equal to the weight of the air displaced by the balloon. assuming that the balloon is at sea level, where the air density is 0.002377 slug/ft3, calculate the maximum weight that can be lifted by the balloon. note: the molecular weight of air is 28.8 and that of helium is 4.

The free body diagram shows a box being pulled to the left up a 25-degree incline. the magnitude of the normal force is