As we know that Heisenber's uncertainty law gives that
[tex]\Delta x * \Delta P = \frac{h}{4\pi}[/tex]
here we know that
[tex]\Delta x = uncertainty In Position = 0.12 mm[/tex]
[tex]\DeltaP = uncertainty In Momentum = m*v[/tex]
now from the above formula we will have
[tex]0.12 * 10^{-3}* 32*10^{-3}v = \frac{h}{4\pi}[/tex]
[tex]3.84*10^{-6}*v = \frac{6.6*10^{-34}}{4\pi}[/tex]
[tex]v = 1.37 * 10^{-29}m/s[/tex]
so above is the uncertainty in the speed