The graph shows the function f(x). Which value is closest to the average rate of change from x = 1 to x = 3?

−3.5,
​​−2.3,
​​−1.8,
​​−0.3,

You work for a landscape company that just got a contract to re-mulch a park. the area that needs mulching is 30 feet by 60 feet. they want a 3 inch layer of much on the area. the company has bags of mulch that cover 2 cubic yards that cost $4.00 per bag. how much will it cost the consumer just in materials to re-mulch the area (round to the nearest dollar)?