When hurricane katrina shut down many oil refineries, the supply curve for oil

a. shifted to the left
b. shifted to the right
c. stayed the same
d. became equal to zero

Option A

Explanation: In simple words, supply refers to the quantity that the producer is willing to offer and sell to the market at a given price. When the natural calamity shuts down the oil refineries the ability of the producer to supply oil will decrease eventually leading to decrease in supply.

The decrease in supply will shift the supply curve to the left. Hence the correct option is A.

i would say their habit of breaking down.

answer; ///(d); determining who competes most closely   with whom evaluating whether industry driving forces and competitive pressure favor some strategic groups and hurt others, and ascertaining whether the profit potential of different strategic groups varies due to the strengths and weaknesses in each groups respective market positions;