According to the 10% rule, it is healthiest to
from the highest trophic levels.
from the lowest trophic levels.
from all the trophic levels.
there are different healthy things to eat from any level, so it depends.

Wow this is phrased rather difficult.

My answer would definitely would probably be "C". 

Remember that the 10% rule only applies towards energy. Since energy is no indication of healthiness all trophic levels are healthy in their own way.

Apolar solvent will dissolve the sample of calcium chloride

The answer to this will be from your lab notes/procedure. it would be best to ask another student who participated in the lab as we do not know what was done, what enzyme or if the temperature is celsius or fahrenheit. if i were to guess though i'd say the rate stopped due to enzyme denturing at high temperature