Answer
The required potential difference is $~~7.0\times 10^4~V$
Work Step by Step
In part (c), we found that the kinetic energy is $~~2.25\times 10^{-14}~J$
We can find the required potential difference:
$K = q~V$
$V = \frac{K}{q}$
$V = \frac{2.25\times 10^{-14}~J}{(2)(1.6\times 10^{-19}~C)}$
$V = 7.0\times 10^4~V$
The required potential difference is $~~7.0\times 10^4~V$
