Conlan wants to answer the question, “does phosphorus affect tomato fruit production? ” which statement represents a hypothesis that he can test to answer his question?
if phosphorus affects tomato fruit production, then tomatoes that are fertilized with phosphorus will have larger leaves.
if phosphorus affects tomato fruit production, then phosphorus should be added to the soil during planting.
if phosphorus affects tomato fruit production, then adding phosphorus to the soil will make tomatoes taste better.
if phosphorus affects tomato fruit production, then plants that are fertilized with phosphorus will produce more tomatoes.

in addition to spreading humanist ideas, erasmus has contributed to criticism of corruption in the church.

the relative atomic mass of an element is the mass of one atom of that element, relative to 1/12th of the mass of a  1212c atom. to convert to an absolute mass in kg, it is necessary to multiply by  1.661×10−271.661×10−27.

the relative atomic mass is roughly equal to the number of neutrons, plus the number of protons, in the nucleus of the atom.

for elements with more than one stable isotope (different types of nucleus with different numbers of neutrons but the same number of protons), the quoted mass is usually the average mass, weighted by the relative abundance of the different isotopes.