A geologist examining a road cut at this location would recognize that Layer A is than Layer B. This conclusion is made through the principle of

First box option: older, younger
Second Box Options: superposition, uniformitariania, original horizontality

Lactase is essential for digesting lactose in milk. this enzyme is specific for this sugar. why? molecules and active sites vary in size; only properly sized molecules can fit.there is a precise compatibility between the active site and the lactose molecule.specificity refers to the action of the enzyme, such as hydrolysis, and relatively few molecules can be hydrolyzed.reaction-specific enzymes assume a fit by folding around the most numerous substrate molecules.