Please show all your work, as your method is as important as your solution.

Please show all your work, as your method is as important as your solution. 

(1)            4(3t + 4) - 20 = 3 + 5t

(2)     

(3)           Interest Problem (important for house or car loans!)

$3,000 is invested at 6% annual simple interest

 How much (x) should be invested at 9% annual simple interest so the total yearly income for both investments is $585?

(4)           'College Hunks Movers' charges $90 plus $25 per hour to move the average student out of the off-campus housing at University of Maryland.  'Two Men and a Truck Movers' charges $40 per hour for the same move. What length of time does it cost less to hire College Hunks Movers over Two Men and a Truck Movers? Show a test case to prove your findings.