Can you buy a piece of a shopping mall? See question No. 3 Real estate is an important component of the U.S. and global economies. For many Americans, homeownership doubles as a first investment. Beyond a primary residence, investors also can buy into the commercial real-estate market: Office buildings, multifamily housing, hospitals, parking lots, storage facilities, retail properties, call centers, distribution hubs, hotels and restaurants form a sector with its own economic ups and downs. In 2016, the S&P 500 recognized real estate as its own sector, separating it from financial services where it had been buried for years—a move some view as a portent of more real-estate investment to come and that others view with indifference. Currently, real estate accounts for less than 5% of the S&P 500 by market cap. How much do you know about real estate—and real-estate investing? 1. What foreign country’s investors are buying the most U.S. commercial real estate? A. C...