Stocks got a lift from two August economic reports, one showing that inflation remained tame and the other showing that Americans spent more at stores. Americans increased their spending — roughly 0.2 percent — the Commerce Department reported, but that was half of what economists expected. The sales report was mixed. Shoppers spent more on cars, electronics, and furniture, but not on much else. Wholesale prices also rose 0.3 percent last month, a sign that inflation remains modest. Investors were looking ahead to the Fed’s policy meeting next week when the central bank is expected to decide the future of its bond buying.