During which period of the Paleozoic Era did the first amphibians evolve?

Permian

Devonian

Cambrian

Carboniferous

Which particle is commonly used to initiate a fission chain reaction

Evaluate why acids are able to conduct electricity. Then describe which types of acids are better conductors and why.

A wave has a speed of 50 m/s and a frequency of 10 Hz. Calculate its wavelength.

Which of the following statements best describes the general pattern of composition among the four jovian planets?

Vitamins A, D, E, and K are examples of A water-soluble vitamin. B dry vitamins. C fat soluble vitamins.

A ball rolls down a ramp. The ball has a mass of 1 kg and it has 18 joules of kinetic energy. What is the ball's speed?

Scientists now think high-fructose corn syrup may disrupt appetite control, making people more often o sleep get angry Ceat fast

What are the strengths and limitations of the doppler method?

Voltage can exist without A. current. B. resistance. C. a closed circuit. D. all of these

During a football game, a receiver has just caught a pass and is standing still. Before he can move, a tackler, running at a velocity of 2.60 m/s, grabs and holds onto him so that they move off together with a velocity of 1.30 m/s.