Mitch ate dinner at a restaurant. The bill came to $82. If he left an 18% tip, how much was the tip?

Can any one me with the answers to these questions asap?

If square root x = -7, then x= -49 true or false

The amount spent on food and drink by 20 customers is shown below what is the modal amount spent and the median amount spent? 40 25 8 36 18 15 24 27 43 9 12 19 22 34 31 20 26 19 17 28