The distance a spring stretches is directly proportional to the mass hooked onto the bottom of it. If a spring stretches 1.1 cm when holding a 3-kg weight, how far will it stretch when a 7-kg weight is hooked to the end? A. 0.47 cm
B. 2.6 cm
C. 4.4 cm
D. 3.1 cm

Marcus built a model car that is 4 inches wide. what scale was used to build the car if the actual width of the car is 6 feet? a. 1 in. = 2 ftb. 1 in. = 2.5 ftc. 1 in. = 1.5 ftd. 1 ft = 1.5 in.

Paula makes stained-glass windows and sells them to boutique stores. if her costs total $12,000 per year plus $4 per window for the frame. how many windows must she produce to earn a profit of at least $48,000 in one year if she sells the windows for $28 each? 1. define a variable for the situation. 2. write an inequality that represents her profit. note: revenue is money coming in. cost is money going out. profit is the difference between the revenue and the cost. in other words: revenue - costs profit 3.using words, describe how many windows she must sell to have a profit of at least $48,000.

Why is causation so much more difficult to prove than correlation?