(a)A steel railroad track has a length of 30.0 m when the temperature is 0F. What is its length on a hot day when the temperature is 40.0F? (b) Suppose the track is nailed down so that it can't expand. What stress results in the track due to the temperature change? a) 0.018 m b) 2.20 x 10^8 Pa O a) 0.018 m b) 3.20 x 10^8 Pa a) 0.026 m b) 1.20 x 10^8 Pa a) 0.018 m b) 1.20 x 10^8 Pa