Answer:
10i
Step-by-step explanation:
Since i^2 = -1, and 1000 = 10^3, we can instinctively guess that the answer is 10i. We can validate this by cubing it, yielding 1000i^3, or -1000i.
400
if the train travel in 150miles in 3hr then\
150/3=50miles a hr
50 x 8 = 400 miles
39.8, $51.00