Answer:
1. 3D-1200 = value after two years.
2. $1800 = value after two years
Step-by-step explanation:
When the value of D triples, 3 times D = 3D. value of the stock after two years decreased, would be the -1200.
When you get the value of 1,000 you can plug it in to get 3 (1000) - 1200 = Stock price after two years