b
(B)\( \,\,\Delta X\, \times \,\Delta P\,\, = \,\,\frac{h}{{4\pi }}\,\,\,\)

\(\therefore \,\,\Delta x\, \times \,m\, \times \,\Delta v\,\, = \,\,\frac{h}{{4\pi }}\,\,\,\)

\(\therefore \,\,\Delta v\,\, = \,\frac{h}{{4\pi \, \times \,\Delta x\, \times \,m}}\,\, = \,\,\frac{{6.626\, \times \,{{10}^{ - 34}}}}{{4\, \times \,3.14\, \times \,0.25\, \times \,{{10}^{ - 5}}}}\,\, = \,\,2.1\, \times \,{10^{ - 29}}\,m/s\)