Marqeta, an Oakland-based payments startup, has raised over $150 million in funding from a single investor. The company is now valued at $4.3 billion, more than double the company's worth from a year ago.  Marqeta is coming off the best two months in the history of the company, deeply embedded in the On Demand economy. Jason Gardner, Founder and CEO of Marqeta, explains how his company has succeeded during the crisis and what his plans are in regards to going public.