Answer
$4.77\ min$
Work Step by Step
The first rate-constant is $k_1=1/(3\ min)=0.333\ min^{-1}$
From the Arrhenius equation:
$\ln(k_2/k_1)=-E_a/R(1/T_2-1/T_1)$
$\ln(k_2/0.333\ min^{-1})=-52000/8.314(1/363-1/373)$
$k_2=0.21\ min^{-1}$
$t_2=1/k_2=4.77\ min$
