Answer:
The unit price is the cost per unit of an item or the cost/price for each item.
1) 4$ per pound. By simplifying the proportion (constant ratio) between the cost, and the pounds of apples. 3 pounds of apples cost 12$ → 3/3 pounds of apples cost 12/3$ → 4 dollars for every pound.
2) 2$ per pound. By evaluating the rate of change (change in the y over x or dependent variable over independent) in the equation: y = 2x. y is the cost in dollars, and x is the pounds of apples. So there are 2 pounds (weight) of apples for every dollar.
3) 3$ per pound. Given a graph with a y scaled by 3, and an x scaled by 1 with a graph y = x or 1 unit up for every unit right. This must be equivalent to y = 3x. Where y is labeled as the cost in dollars, and x as the weight in pounds. So there are 3 dollars for every pound of apples.
4) Store B. Because 2 is less than 3 which is less than 4.
