A radioactive isotope of the element potassium decays to produce argon. If the ratio of argon to potassium is found to be 31:1, how many half-lives have occurred?

A nebula is a concentrated area of gas and dust. How does this relate to the formation of stars within galaxies?

Suppose you made some beef soup. you want to separate the extra fat from the soup before you eat it. how could you do that?

Which of the following is a chemical equation that accurately represents what happens when sulfur and oxygen are produced from sulfur trioxide? A. 2S + 3O2 - - > 2SO3 B. 2SO3 - - > 2S + 3O2 C. S + O2 - - > SO3 D. SO3 - - > S + O2

When a body receives a stimulus, the nervous system is called to release adrenaline. under what circumstances can this happen?

Which of the following is an example of a plasma A. An electric spark that is seen, then disappears

A lizard accelerates from 2 m/s to 10 m/s in 4 seconds. what is the lizard average acceleration

Explain the difference between balanced forces and action and reaction forces.

Describe and apply Newton's Three Laws

If you do 1000j of work on a system and remove 500j of heat from it, what is the change in its internal energy

Two children stretch a jump rope between them and send wave pulses back and forth on it. The rope is 4.5 m long, its mass is 0.42 kg, and the force exerted on it by the children is 71 N.