Answer
$R=1.51mm$
Work Step by Step
We know that,
$R=\frac{mv}{qB}$
We plug in the known values in this equation to obtain:
$R=\frac{9.109\times 10^{-31}(2.6507\times 10^7)}{1.6\times 10^{-19}(0.100)}$
$R=0.00151$
$R=1.51\times 10^{-3}$
$R=1.51mm$
