What form of nitrogen are most plants able to absorb

A man is standing on the shore of a beach, up to his knees in water. Every 5 seconds a wave breaks on him. What is the period of the wave? a. 12 waves per minute c. 5 seconds b. 5 hertz d. 0.2 hertz

Which of the following classifications of star temperature is coolest?

Why did corn borers increase after the fields were sprayed for beetles? had more corn to eat their natural predator was gone were protected by the spray

If a spacecraft travels 3.6 au per year, in how many years would it travel from earth to mars? a. 0.15 years b. 1.83 years c. 2.54 years d. 3.72 years

The fastest plane ever made, the Lockheed SR71, was able to travel 2200 miles per hour. Based on this speed, how far can it travel in 2 hours, 3 hours, and 5 hours?

True or False? a globular cluster is a group of older stars that are clustered together.

The doppler effect is the change in observed frequency due to

Which of the following is NOT a vector quantity? (A) Acceleration (B) Average velocity (C) Linear momentum (D) Potential energy (E) Force

Which of Newton's laws of motion is demonstrated by a hammer pounding a nail into a board

Heated air molecules in a hot air balloon soon carried thermal energy to the top of the balloon. this is an example of ... conduction. Convection. Radiation. Cooling.