Which of these events during the modern environmentalism era was the result of a town constructed on a chemical waste dumpsite, and raised awareness of the problem of hazardous
waste disposal?
a. Love Canal
b. Nuclear testing in the Marshall Islands
c. The Donora fluoride smog
d. The burning of the Cuyahoga River

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

: -)

answer: substrate concentration. enzymes work best when there is a high enough substrate concentration for the reaction they catalyse.