Atoms of element A decay to atoms of element B with a half-life of 20,000 years. If there are 10,000 atoms of A to begin with (and 0 atoms of B), how long will it take for there to be 2,500 atoms of A?

D is at rest at the top of a 2 m high slope. The sled has a mass of 45 kg. The sled's potential energy is J?

Four large grocery food chains sell approximately how much of the nation's food? one-fourth one-half three-fourths 100 percent

A force F = (cx - 3.00x^2) i^ acts on a virus as the virus moves along an x axis, with F measured in Newtons, x in meters, and c a constant. At x = 0, the virus’s kinetic energy is 20.0 J, while at x = 3.00 m, it is 11.0 J. Find c.

8. How does the direction of friction compare to an object's direction of motion?

According to the diagram shown on the right, how does energy flow in an ecosystem? A. Energy flows from producers to the Sun and from producers to consumers. B Energy flows directly from the Sun to both producers and consumers.

In a class debate, a student argues that the big bang theory is "just a theory." What is most likely to be this student's understanding of scientific theories? A. Theories agree with observations of nature. B. Theories are just guesses. C.

Look at the advertisement. A poster that reads, "There's more to resistors than resistance. If you're really serious about cost, be serious about quality." with tools. Which persuasive media technique is used in this advertisement

If you were told an atom was an ion, you would know the atom must have a

When a potential difference of 13 V is placed across a resistor, the current in the resistor is 1.4 a. What is the resistance of the resistor?

Person with a mass of50 kg jumps up from the earth with an acceleration of 20 newtons. what is his acceleration?