From the passage below, extract the names of the companies and technologies that Walmart has acquired over the last 3 years.

In the first quarter of 2020, consumers responded to COVID by shopping less frequently (5.6% fewer transactions), and buying more when they did shop (16.5%).[133] As people shifted from eating out to eating at home,[34] net sales at Walmart increased by 10.5%, while online sales rose by 74%. Although Walmart experienced a 5.5% increase in operating expenses, its net income increased by 3.9%.[133] In the third quarter of 2020, ending October 31, Walmart reported revenue of $134.7 billion, representing a year-on-year increase of 5.2 percent.[134]

In December 2020, Walmart launched a new service, Carrier Pickup, that allows the customers to schedule a return for a product bought online, in-store, or from a third-party vendor. These services can be initiated on the Walmart App or on the website.[135]

In January 2021, Walmart announced that the company is launching a fintech startup, with venture partner Ribbit Capital, to provide financial products for consumers and employees.[136]

In February 2021, Walmart acquired technology from Thunder Industries, which uses automation to create digital ads, to expand its online marketing capabilities.[137]

In August 2021, Walmart announced it would open its Spark crowdsource delivery to other businesses as a white-label service, competing with Postmates and online food ordering delivery companies.[114]

In December 2021, Walmart announced it will participate in the Stephens Investment Conference Wednesday, and the Morgan Stanley Virtual Global Consumer & Retail Conference.[138] In June 2022, Walmart announced it would be acquiring Memomi, an AR optical tech company.[139]

In August 2022, Walmart announced it would be acquiring Volt Systems, a vendor management and product tracking software company.[140] Walmart announced it was partnering with Paramount to offer Paramount+ content to its Walmart+ subscribers in a bid to better compete with Amazon.[141]

Walmart announced in August 2022 that locations were not going back to 24 hours with most stores now being open between 6am and 11pm.[142]

In January 2023, Walmart announced it would raise its minimum wage for U.S. hourly workers from $12 to $14 an hour. Approximately 340,000 employees are expected to receive a raise, effective in early March 2023, and Walmart's U.S. average wage is expected to be over $17.50. The company also announced it would be adding additional college degrees and certificates to its Live Better U program.[143]

Walmart acquired Volt Systems in August 2022. Volt Systems focuses on vendor management and product tracking. They also acquired technology from Thunder Industries in February 2021 to create digital advertisements.