A carpenter makes bookshelves. He is studying how much money he can earn in one year. Choose the three variables that are most important for him to study.
A. the weight of each bookshelf
B. the cost of building a bookshelf
C. the dimensions of each bookshelf
D. the time it takes to build each bookshelf
E, the price customers will pay for a bookshelf
J
F. the number of different designs he can build

step-by-step explanation:

step-by-step explanation:

rectangles are made up of 4 right angles, which means that a side and a base meet perpendicular to one another.   their slopes then have to reflect perpendicular slopes.   perpendicular slopes are opposite reciprocals of one another.   for example, if the slope of one line is +2/3, then the perpendicular slope to that would be -3/2.   so we look for that combination in our choices.

all of them satisfy that condition (so what's the question, i guess? )

i don't know i don't know