Rivian Automotive plans to debut its all-electric pickup truck at the Los Angeles auto show on Monday, and its founder and chief executive exudes optimism about his desire to do for the U.S. auto industry's most lucrative segment what Tesla did for luxury cars.

Not everyone is so sanguine.

R.J. Scaringe, Rivian's 35-year-old CEO, said he and his financial backers believe that demand for electric pickups is 'massively underserved.' 

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Rivian Automotive unveiled its all-electric pickup truck at the Los Angeles auto show today.  Rivian's truck will have a range of up to about 400 miles, which would be the longest among its three different battery packs.