Earnings live: Block stock surges after Jack Dorsey cuts 40% of workforce, Duolingo shares drop premarket

Fourth quarter earnings season is entering its final stretch. Earnings from Nvidia (NVDA) this week marked the final company among the "Magnificent Seven" tech stocks to report quarterly results. This report offered a crucial update on how demand for its high-tech AI chips — a big part of the hundreds of billions of dollars its Big Tech peers are spending on AI investments — continues to shape up. But concerns about increased competition and the drivers underpinning Nvidia's strong forecast overshadowed t ...