A $1\mathrm{.}00-kg$ block oscillates with a frequency of $10\mathrm{.}0$ Hz at the end of a certain spring. The spring is then cut into two halves. The $1\mathrm{.}00-kg$ block is then made to oscillate at the end of one of the halves. What is the frequency of oscillation of the block?

a$.,5\mathrm{.}00Hz$

b$.,10\mathrm{.}0Hz$

c$.14\mathrm{.}0$ Hz

d$.20\mathrm{.}0$ Hz

e$.40\mathrm{.}0$ Hz