Which situation is most likely to show a constant rate of change? a. the cost of a new car compared with the number of tires it has b. the outside temperature compared with the time of day c. the weight of a child compared with its age in months d. the distance traveled by a truck driving at a constant speed compared with time

check the picture below.

well, the angle at the vertex d is clearly not a right-angle, let's check for the one at the vertex f which does look like,   however if it's indeed, that means ef is perpendicular to df, in which case their slopes will be negative reciprocal of each other.

so the negative reciprocal of the slope of ef is 1, however the slope of df is not 1, is 1/2, so nope, they're not perpendicular lines.

i do not know this sorry : (