How much time it takes for Krays offrequency $3$x$1018$ Hz to travel $1$ cm$?$

a$)3\mathrm{.}0$ X $10$ to the power $5$ S

b$)3\mathrm{.}3$ x $10-$ to the power of $11$ S

c$)3\mathrm{.}0$ x $10$ to the power of $8$ s

d$)3\mathrm{.}3$ x $10$ to the power of $5$ s