The chart shows the movement of a ball after several seconds. A 2-column table with 4 rows. The first column labeled A has entries 0, 4, 8, 12, 16. The second column labeled B has entries 0, 2.5, 6, 8, 10. Column A is on the x-axis, and Column B is on the y-axis. Which titles should replace A and B? Column A should be “Time,” and Column B should be “Position.” Column A should be “Position,” and Column B should be “Time.” Column A should be “Velocity,” and Column B should be “Speed.” Column A should be “Speed,” and Column B should be “Velocity.” 1

Do you agree with scientist’s prediction about the warming of alaska and other polar regions?

Several mountains together form a mountain . a few of these combined form a mountain system. several systems combined form a mountain , which can stretch thousands of miles in length.

Aheat engine running backward is called a refrigerator if its purpose is to extract heat from a cold reservoir. the same engine running backward is called a heat pump if its purpose is to exhaust warm air into the hot reservoir. heat pumps are widely used for home heating. you can think of a heat pump as a refrigerator that is cooling the already cold outdoors and, with its exhaust heat qh, warming the indoors. perhaps this seems a little silly, but consider the following. electricity can be directly used to heat a home by passing an electric current through a heating coil. this is a direct, 100% conversion of work to heat. that is, 19.0 \rm kw of electric power (generated by doing work at the rate 19.0 kj/s at the power plant) produces heat energy inside the home at a rate of 19.0 kj/s. suppose that the neighbor's home has a heat pump with a coefficient of performance of 4.00, a realistic value. note: with a refrigerator, "what you get" is heat removed. but with a heat pump, "what you get" is heat delivered. so the coefficient of performance of a heat pump is k=qh/win. an average price for electricity is about 40 mj per dollar. a furnace or heat pump will run typically 200 hours per month during the winter. what does one month's heating cost in the home with a 16.0 kw electric heater? what does one month's heating cost in the home of a neighbor who uses a heat pump to provide the same amount of heating?