Find Conductivity, Resistivity and Resistance.

A silicon sample is 0.5 cm long and has a cross-sectional area of (50x10-4)2 cm 2. Find the conductivity, resistivity and resistance of the intrinsic sample. If the same sample is doped with a donor impurity to an extent of 1 atom per 10 6 atoms of silicon, find the new values of conductivity, resistivity and resistance and compare the results.
Assume T = 300 K, n i = 1.45 x 1010 cm-3, n = 1500 cm2/V-s, p = 475 cm 2/ V-s,
e = 1.6 x 10 -19 C and concentration of silicon atoms, n V = 5 x 10 22 cm -3