5. A wheelbarrow contains two simple machines—a lever and a wheel and axle. For a certain wheelbarrow, the lever has an efficiency of 72 percent, and the wheel and axle has an efficiency
of 64 percent. What is the overall efficiency of the wheelbarrow?

The eel has a certain amount of rotational kinetic energy when spinning at 14 spins per second. if it swam in a straight line instead, about how fast would the eel have to swim to have the same amount of kinetic energy as when it is spinning?

How many astronauts have walked on the moon?

Use the library or internet to research each planet. make a chart comparing the following: approximate surface temperature relative surface gravity compared to earth atmospheric gases water in any form: solid, gas, or liquid when you have completed your chart, use the information you have collected to answer the following questions: which is the hottest planet? which is the coldest planet? which planet's temperature is closest to that of earth? (note: water boils at 100°c/212°f. water freezes at 0°c/32°f) which planet has the greatest gravitational attraction? which planet has the least gravitational attraction? which planet's gravitational pull is closest to that of earth? do any of the planets have oxygen in their atmosphere? which planet's atmosphere most resembles that of earth? do any of the planets have flowing water? which planet's water resources (solid, gas, or liquid) might be close to the amount on earth? which planet most resembles earth in terms of all of the factors: temperature, gravity, atmosphere, and water? if earth became an uninhabitable planet, which planet do you think would be the next best to live on? explain your answer.