5th Grade Math (Please help!)

The last time i bought this product , it cost $20.00 but it looks like it cost 29. 60 today? what is the increase

Use the four functions below for this question. compare and contrast these four functions using complete sentences focus on the slope and y- intercept first, and then on any additional properties of each function

F(x)=5/6x+3 which of the following is true