Can you help me understand this problem?

In t years from now, one investment is earning a profit at a rate of p' (t) in thousands of dollars per year while a second investment is earning profits at a rate of p' (+) also in thousands of dollars per year. Interpret the fact that 15 (Pi - P2)(t) dt = 10 o The investment will earn $ thousand more than the investment in the next years. (5 points)