What is free nitrogen?

A.) nitrogen that is ready for plants to use
B.) nitrogen that has been fixed by bacteria
C.) nitrogen that cannot be used by organisms
D.) nitrogen that is returned to the soil by decomposers
THE ANSWER IS C.)

50 g of ice at 0°c is dropped in a beaker containing 100 g of water at 0°c. what will be the contents of the beaker after 5 hours? assume that the room temperature is 0°c.

The long handle on a rake is a(n) a. lever b. screw c. wedge d. inclined plane

Total solidification times of three casting geometries are to be compared: a sphere, a cylinder, in which the length-to-diameter ration - 1.0, and a cube. volume = 1000 cm^3 for all three shhapes, and the same casting alloy is used. a) determine the solidification times of each geometry b) based on the results of part (a), which geometric element would make the best riser? c) if the mold constant = 3.5 min/cm^2 in chvorinov's rule, compute the total solidification time for each casting.