At what temperature will silver have a resistivity that is four times the resistivity of tungsten at room temperature?

 resistivity Ag 15.9e-9 Ω-m
resistivity Fe 100e-9 Ω-m
temperature coefficient of resistivity
α = 0.0038/ºC Ag

R = R₀(1 + α∆T)
4*100 = 15.9(1 + (0.0038)∆T)
400/15.9 = 25 = 1 + (0.0038)∆T
(0.0038)∆T = 24
∆T = 6357ºC
add 25º to get 6382ºC

 I believe

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.