A boy drops a stone from a cliff, which reaches the ground in 20 seconds. Calculate the height of the cliff.

A wave is traveling at a speed of 15 m/s and its wavelength is 3 m. Calculate the wave's frequency.

Calculate the efficiency of a fossil-fuel power plant that consumes 380 metric tons of coal each hour to produce useful work at the rate of 720 MW. The heat of combustion of coal (the heat due to burning it) is 28 MJ/kg.

A mummy is discovered that has only one-fourth of its original carbon-14 remaining. How old is the mummy, in years? Explain your reasoning.

raising the temperature of a gas _ it's pressure if the volume of the gas and the number of particles are constant

What formal regions are located in the western hemisphere

If the mass of an object is 84g and the volume is 12cm3 what is the density

Describe one example of competiton of tropical dry forest

What is the center of a tornado called A. the eye B. The center C. The middle road D. The vortex

Is it legal in Florida for a math teacher forces the kids to do push ups?

Acceleration is best defined as the rate of change of blank of an object