)a 1.50 {\rm m} cylindrical rod of diameter 0.550 {\rm cm} is connected to a power supply that maintains a constant potential difference of 15.0 {\rm v} across its ends, while an ammeter measures the current through it. you observe that at room temperature (20.0 ^\circ {\rm c}) the ammeter reads 18.8 {\rm a}, while at 92.0 ^\circ {\rm c} it reads 17.4 {\rm a}. you can ignore any thermal expansion of the rod.

1.find the resistivity and for the material of the rod at 20 ^\circ {\rm c}. (rho= ? ω*m)

2.find the temperature coefficient of resistivity at 20 ^\circ {\rm c} for the material of the rod.(α= ? (c)^-1)