Simple exponential smoothing is being used to forecast demand. The previous forecast of $66$ turned out to be six units less than actual demand. The next forecast is $66\mathrm{.}9,$ implying a smoothing constant, alpha, equal to:

Group of answer choices:

A$)0\mathrm{.}09$

B$)0\mathrm{.}10$

C$)0\mathrm{.}25$

D$)0\mathrm{.}60$

E$)0\mathrm{.}15$