https://www.reuters.com/article/us-tesla-truck/tesla-unveils-electric-big-rig-truck-in-midst-of-model-3-factory-hell-idUSKBN1DG1LW >Tesla Inc on Thursday unveiled a prototype electric big-rig truck that it will start producing in 2019, throwing itself into a new market even as it struggles to roll out an affordable sedan on which the company's future depends.