Which two gases in the atmosphere are essential to life on Earth? *

Nitrogen and Helium

Oxygen and Carbon Dioxide

Neon and Argon

Hydrogen and Helium

The 5 physical fitness

Which best describes how magnesium and oxygen bond? a. they form an ionic bond by exchanging two electrons. b. they form an ionic bond by exchanging three electrons. c. they form a covalent bond by sharing one electron. d.

The attractive force between a negatively charged particle (electron) and a positively charged particle (proton) is greater on the

The A 400 kg spacecraft has a momentum of 30,000 kg·m/s up. What is the velocity? A. 12,000,000 m/s B. 1200 m/s C. 300 m/s D. 75 m/smass of a baseball stays constant. As the velocity of the ball increases, what happens to the momentum of the ball?

Which term describes a possible explanation of, or answer to, a scientific question that is based on prior knowledge or research and that is testable?

How would life on earth be different if earth's axis were not tilted with respect to its orbit? A. There would be no seasons. B. There would be no day and night. C. All places would have the same climate. D. The seasons would be much shorter.

What will a spring scale read for the weight of a 75.0-kg woman in an elevator that moves upward with constant speed of 5.8 m/s?

What's the definition of: • cellular respiration • photosynthesis

What are the steps that are important to take for your safety during an earthquake? a. stay away from walls and windows c. stay away from electrical and gas lines b. get under a desk or table d. all of the above

You have an open air column of length 1.40 m in air at 24.2 °C. What is the frequency of the third harmonic?