Pls help ah pls help help ASAP

y=2x−1 5x−4y=1 is (1,1)(1,1) a solution of the system?

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)?

In june 2003, an italian named giancarlo bellingrath set a world record when he held his breath for 12 minutes and 47 seconds. how many milliseconds over 12 minutes was he?