A total cost function is given by T = 230 + 5,733/Q, where Q is the quantity in units At what quantity (Q) will the total cost (T) be minimised? Answer to nearest whole number.

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.