Answer:
t = 9.88 (since units are not given we cannot write those, could be seconds, minutes or months etc)
Explanation:
For continuous compounding interest, we have the formula,

where P(t) is the value at time t
t is time
A is the original amount
r is the rate
In our case,
r = 2.5% = 0.025
A = 12,500
P(t) = 16,000
And we have to find t, so,

t = 9.88 (since units are not given we cannot write those, could be seconds, minutes or months)