ANASTASIA MOLONEY ON Monday, Steven Preston, who heads a non-profit helping vulnerable Americans find jobs, received a call from MacKenzie Scott, the billionaire ex-wife of Amazon founder Jeff Bezos. Scott, the world's 18th-richest person, told Preston she was donating $20 million to his organization - Goodwill Industries International - which helps people of color, people with disabilities and people without a high school diploma, among others, find work. In the past four months, Scott has donated more than $4 billion to food banks and emergency relief funds fighting the impact of the coronavirus pandemic. The Thomson Reuters Foundation spoke to…