Approximately How Long Will It Take an Investment Of $\$ 300$

Multiple Choice

Approximately how long will it take an investment of $\$ 300$ to triple, if the interest rate is $3.5 \%$ Per year compounded continuously?

A) $3.5 \text { years }$
B) $21 \text { years }$
C) $13 \text { years }$
D) $31 \text { years }$
E) $9 \text { years }$