Resolution authorizing the Office of Contract Administration to execute Amendment No. 4 to Contract 1000018631 between the City and County of San Francisco and W.W. Grainger, Inc., for the purchase of industrial supplies for City departments, increasing the contract amount by $8,800,000 for a total contract amount not to exceed $20,900,000 and extending the term by one year for a total contract duration of July 15, 2020, through December 31, 2023.