A farmer is digging a cylindrical tunnel to drain the lake on his land. If he makes a scale model that is 4 inches high with a radius of 8 inches and the scale is 1 inch per 2 feet, approximately how much water would the tunnel hold at any time?
(The formula for the volume of a cylinder is r2 × height)

Which process does not require the presence of a physical substance in order to transfer heat? air in the atmosphere is heated by the ground. this warm air then rises, and cooler air falls. this is an example of what type of process? how is conduction different from radiation?

Consider a culture medium on which only gram-positive organisms such as staphylococcus aureus colonies can grow due to an elevated nacl level. a yellow halo surrounds the growth, indicating the bacterium fermented a sugar in the medium, decreasing the ph as a result and changing the color of a ph indicator chemical. this type of medium would be referred to as a differential and enrichment culture.

2. what two items do autotrophs take from the environment to produce their food? 3. what are the two items that are released during transpiration from leaves? 4. what are the two membranes of the system? a. what are the two stages of photosynthesis? what are the two parts of photosynthesis?