Yall i forgot what 10×10 is. help m​

Question and answers are in the attached picture. you so much in advance.

If eh = hg and hg=16, find the diameter of k

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.