An Olympic runner completes the 200-meter sprint in 23 seconds. What is the runner's average speed? (Round your answer to the nearest tenth of a meter per second.)

Which scenario represents the weakest force? (Assume particles in all scenarios are the same distance apart.) Protons and neutrons are held together inside the nucleus. Two particles are attracted to one another by static electricity.

A particle has two down quarks and one up quark. What is the charge of that particle?

The earth takes 1 year to revolve around the sun at 1 A. U. distance (an astronomical unit = 93,000,000 miles). If a planet were 4 A. U. from the sun, how many years would it take to make 1 orbit?

Uranium has two naturally occurring isotopes. 238u has a natural abundance of 99.3% and 235u has an abundance of 0.7%. it is the rarer 235u that is needed for nuclear reactors.

What is evaluating? O A. Making up evidence about something O O B. Making something biased C. Making something more complicated O D. Drawing a conclusion about something

Which of these changes does a submarine encounter as it returns from the bottom of the ocean to the surface of the ocean? a. the amount of sunlight increases. b. the water temperature decreases. c. the amount of plants decreases. d.

Why do some elements have symbols that don't use letters in the element's name?

How many (whole number of) 91 kg people can safely occupy an elevator that can hold a maximum mass of exactly 1 metric ton? A metric ton is 1.000 * 103 kg. Answer in units of people.

What are the two types of surface waves? How are they different and which one would cause more damage? Explain.

What causes a regular reflection?