Determine the value of u for a three period binomial problem when the option$$s life is one$-$half a year and the volatility is $0\mathrm{.}48.$ Use the model for u that does not require the risk$-$free rate.$$ a$.1\mathrm{.}22$ b$.1\mathrm{.}48$ c$.1\mathrm{.}40$ d$.1\mathrm{.}32$ e$.$ none