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1a. A bicycle and a rider have a combined mass of 250 kg. How many calories of heat are generated in the brakes when the bicycle comes to a stop from a speed of 25 m/s? Take 4.18 J=1cal [5 pts] b. If all the energy, Q, is trapped in a 1500 g bag without any heat loss, how much will its temperature increase (AT)? Give your answer to the nearest integer. Assume the specific heat of bag, c = 0.250 cal/g °C. [5] 2. A 200 kg person who has been watching his weight mistakenly consumes an order of French fries (350,000 calories) and wishes to work off the energy by climbing a 25.0 m stairway. a. What will be his/her potential energy at the top of the stairs? [5] b. How many calories will equal the PE? [5] c. How many vertical climbs are needed to use all the energy? [5] 1cal = 4.18 J, g = 9.8m/s².

3.The table shows the primary energy consumed in the US annually. Percentage % 36 27 8 18 11 Source Petroleum Natural gas Nuclear Coal Renewable a. If the United States spent $ 200 billion annually on energy uses, calculate how much will be spent on fossil fuels alone. [5] b. Temperatures on Triton, one of Neptune's moons is about -255 °C. What is the temperature in i. Fahrenheit [5] ii. Kelvin [5] I