Which device uses AC current to operate?

A. locomotive train

B. desktop computer

C. car

D. portable media player

E. flashlight

Is there 1,000 more milky way in the galaxy? If it is true is there life also? Are aliens real?

How is the modern model of an atom different from the bohr atomic model?

A bulldozer does 4,500 J of work to push a mound of soil to the top of a ramp that is 15 m high. The ramp is at an angle of 35° to the ground. How much force did the bulldozer apply to the mound of soil? Round your answer to two significant figures.

Scientist do their work by using inquiry. Inquiry is:

What two types of matter are closest in density? how do you know?

During a medical condition screening lung capacity testing is a standard procedure. True of false

Which of the following is a unit of energy found in food? a). vitamin b) calorie c) nutrient d) water

As one goes from left to right in a period, which of the following is true? A. The number of protons decreases. B. The number of valence electrons increases. C. both A and B D. none of the above

Which of the following surfaces reflects the most light A yellow cloth B. tree trunk C aluminum foil D. Concrete sidewalk

Which part of an atom has a mass approximately equal to 1/2000 of the mass of a common hydrogen atom? A. nucleus B. electron C. proton D. electron cloud