Can anybody help me and explain this to me please

What is the length of bc ? enter your answer in the box. bc =

What is the area of triangle abc if a = 8, b = 11, and c = 15?

The spring the owner of a sporting good store decreases the price of winter gloves from $10 to $8 each increases the price of swimming goggles from $8 to $10 without doing the math you think the percent decrease in the price of the gloves the same as the percent increase of the goggles explain why or why not