Ben is monitoring a colony of bacteria. Initially, the colony consists of 159 bacteria. The following function represents the number of bacteria in the colony after x hours. Which expression approximately represents the number of hours, x, it takes for the number of bacteria in the colony to reach 168?

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)?