A skateboarder is going to ride down one ramp and then up another. She wants to come down the first ramp and go up the second ramp to a height of exactly 3 m without kicking off or adding any other energy. Together the skateboard and skateboarder have a mass of 72 kg, and she will lose approximately 210 J of energy to friction. g = 9.8 m/s^2. Calculate the required starting height of the skateboarder in order for her to reach 3 m.

Astudent looks at ocean waves coming into the beach. an ocean wave with more energy will a) have a greater height. b) have a greater period. c) travel toward the beach faster. d) strike the beach with greater frequency.

Ineed this now one scientist feels that the changes in global climatic patterns may be good for the health of the biosphere. another scientist feels that sharp changes in climatic patterns could result in the extinction of the biosphere. which of these is the most likely reason the two scientists gave conflicting opinions on the impact of changes in the global climatic pattern? they do not have enough knowledge on the topic. they did not discuss the issue among themselves. they believe conflicting opinion strengthens science. they study different areas of science and have different scientific focuses.

Which of the following is a direct benefit of the use of assembly lines in production a. laws against theft fraud and coercion are needed to protect free choice. b. the government needs to plan efficient outcomes. c. competition among producers by itself cannot ensure a wide range of consumer choices. d. works pressure the government to guarantee minimum wages