Plz help due wednesday with alot of questions

What is the value of 1/3x + 7x when x = 5

Steve wants to develop a way to find the total cost of any item including sales tax. the sales tax in his city is 6%. his friend jenna writes the expression x + 6x where x is the cost of the item. explain whether her expression is correct based on the situation.

Enter the missing numbers in the boxes to complete the table of equivalent ratios.time (min) distance (km)? 36 9? 1512 ?