Tesla Inc. stock fell on Friday after the unveiling of a souped-up version of its Model S sedan late Thursday, but the stock held on to gains around 1.3% for the week. The Model S, a sedan first sold in 2012, has lost ground to Tesla’s cheaper sedan, the Model 3, and the newest offering, the compact SUV Model Y. The “Plaid” version of the Model S, which had its interior redesigned and is faster and more expensive, is also a few months late to get to market, and the Thursday event itself was more
