$(10).$ If it takes $4\mathrm{.}0$ N to stretch a spring $6\mathrm{.}0$ cm and if the spring is then cut in half, what force does it take to stretch one of the halves $3\mathrm{.}0$ cm $?$

a$.2\mathrm{.}0$ N

b$.4\mathrm{.}0$ N

c$.8\mathrm{.}0$ N

d$.16$ N