Steven investigates the amount of damage to the head gaskets on the trucks in his fleet and finds that the damage index depends on the ambient temperature. he develops the equation y = -2/3x + 14 to model the relationship. if the temperature increases 1 degree, what happens to the damage index for the head gasket?
a) it decreases by 14 points.
b) it decreases by 21 points.
c) it decreases by 0.047 points.
d) it decreases by 2/3 of a point.