99 percent of the earth's atmosphere by mass is made up of only elements. These elements are

A) Carbon and oxygen

B) Nitrogen and oxygen

C) Hydrogen and oxygen

D) Helium and hydrogen

How many excess electrons must be present on each sphere if the magnitude of the force of repulsion between them is 4.57*10-21 newtons?

true or false? constructive interfernce occurs when a crest meets up with another crest at a given location along the medium

What is the relationship between mass and weight in terms of formula

Two identical loudspeakers are placed on a wall 3.00 m apart. A listener stands 4.00 m from the wall directly in front of one of the speakers. A single oscillator is driving the speakers at a frequency of 300 Hz.

An optic fiber is made of clear plastic with index of refraction of 1.50. for what angle of incidence will light remain within the plastic "guide"?

A hot air balloon is rising straight up at a constant speed of 7 m/s. when the balloon is 12.0 m/s above the ground, a gun fires a pellet straight up from ground level with an initial speed of 30.0 m/s.

The atmosphere is an). O element O molecule O mixture O compound

What is the velocity of the car, in meters per second, just after it hits a 135-kg deer initially running at 10.5 m/s in the same direction? Assume the deer remains on the car.

True or false the metric unit used to describe weight as a measure of the force of gravity is called a newton

One car travels 40. meters due east in 5.0 seconds, and a second car travels 64 meters due west in 8.0 seconds. During their periods of travel, the cars definitely had the same