Find the difference: 7 7/8 - 3 1/4=? *

The price of a particular stock is represented by the linear equation , where x represents the number of weeks the stock has been owned and y represents the price of the stock, in dollars. if this relationship continues, what is the price of the stock after it has been owned for 12 weeks? $92.55 $94.37 $100.52 $114.39

Which expression is not a polynomial?

[10 points, algebra 2]according to my answer key the restrictions are -1 and 4. but why not positive 1?