Question

Please help me with number 7.

Answer 1

7a expression: 12 + (- 1) + (- 1) + 3
7b evaluate: 13                    Solving:((12 + -1 = 11) + (-1 + 3 = 2) (11 + 2 = 13)) 
7c: At the end of the three days, the value of the stock was $13.