F   the amount of carbon dioxide in each container

D   the type of weed-control cloth

D   making sure to test one variable while controlling all others

A   lengths of the fish

F   use equal string lengths and different plumb bob masses

C   stopwatch

A   the temperature inside the boxes

J   light microscope and slides

A   Graduated Cylinder

J   use a third dish that doesn’t receive X-rays or sunlight.

C   Areas at the beach have the most stable temperatures.

* An initial sharp increase that slows down or levels out.

C   At higher air temperatures, more water evaporates.

D   plant in box D

H   driving automobiles less often

D   Every 180 grams of sugar added to a liter of water causes the boiling point to increase by 0.5^oC.

J   Levels of oxygen in the water decrease.

C   so his efforts could be correctly replicated when it worked.

J   feed some cats with the specific brand of cat food and other cats with another brand.

*Comparison

B   Which sponge is the most absorbent?

H   If iron is added to the hydrotonic solution, the lettuce will grow at a faster rate.

H   Does an element's density increase as its atomic mass increases?