Hydroelectric power is a good source of heat energy.

a. true

b. false

When a wave crosses a boundary and changes speed and direction?

Where is most of the mass of an atom located? a. in the nucleus b. in the orbits c. in the electrons d. it is split between the nucleus and the orbits

An ambulance is traveling east at 61.9 m/s. Behind it there is a car traveling along the same direction at 28.5 m/s. The ambulance driver hears his siren at a frequency of 694 Hz. 28.5 m/s Car 61.

A hunter fires a gun and hears an echo from a cliff face 5 s later. He knows the cliff is 850 m away. How fast is the sound travelling where the hunter is

If timmy is traveling 20 miles per hour south for 2 hours. How far is he displaced

Which of these is the best reason for proper nutrition? A. To ensure that you will be skinny B. To protect yourself against certain diseases C. To improve your intelligence D. To ensure that you will get good grades

And object has a mass of 15g it has a volume of 7.5ml. find the density of the object.

I need this answered quickly. is the branch of science for naming and classifying organisms based on their natural relationships? A-physics B-taxonomy C-genetics D-biology

For a fixed amount of gas, if the absolute temperature of the gas is doubled, what happens to the pressure of the gas?

A 500-kilogram sports car accelerates uni- formly from rest, reaching a speed of 30 me- ters per second in 6 seconds. What distance has the car traveled during the 6 seconds?