[填空题]
A 5.80-m length of 2.1b1gfr95oejvwfap 5jrh ( ya) 3lij( 50-mm-4sehf(m-hu n)ur s(vt4vo q/ /diameter wire carries a 750-mA current when 22.0 mV is applied to its ends. If the drift sotqf s-m nh/ 4h /(ve4u)u(vsrpeed is $ 1.7\times10^{-5 }\;m/s$, determine
(a) the resistance R of the wire, $\approx$ $\Omega$(retain three decimal places)
(b) the resistivity $\rho$. $ \times10^{-8 }\;\Omega\cdot m$
(c) the number n of free electrons per unit volume. $ \times10^{28 }\;e^-/m^3$
