Answer:
7 years
Explanation:
Given : An initial investment of $200 is now valued at $350. The annual interest rate is 8% compounded continuously.
The equation represents the situation, where t is the number of years the money has been invested.

To Find : About how long has the money been invested?
Solution:

We are supposed to find the value of t using calculator



So, t ≈ 7 years.
Hence the money has been invested for 7 years.