Morning Money Memo…

Was last week's stock market plunge just a two-day tumble or a true sign of worry? Some market watchers say the rout is a buying opportunity, pointing to signs of improvement for both the US economy and Japan's return to growth.

Stock futures rose this morning, but with rising volatility and emerging market turmoil, Wall Street is on edge as the new trading week begins. The S&P 500 - the benchmark for many stock mutual funds - dropped 2.6 percent last week. The Dow Jones Index opens for business below 16,000.

Asian markets were hit hard today on the possibility of slower growth in China and the likelihood the Federal Reserve will announce a further drop in its bond-buying stimulus Wednesday.

Emerging markets have been propped up for years by investors seeking higher returns using easy money from the Fed and other central banks. Now that these policies may be ending soon, some investors are heading for the exits. The financial crisis in Argentina and the rise in value of the US dollar are playing into investor fears.

This is a busy week for corporate earnings reports. Apple will be the stock to watch later today when it releases its latest quarterly report. Investors will be paying attention to iPhone sales, looking for the previous year's records to be broken. Apple released two new iPhones during the last quarter of 2013. It's also signed new deals with China Mobile - the world's largest cell phone provider - and Japan's top company NTT DoCoMo.

Google announces its quarterly earnings Thursday. While the firm may announce big gains in advertising revenues, Google stock has soared 30 percent in the past three months. Without a blow-out report this week, Google's stock price could sag.

Samsung Electronics it has signed an agreement with Google to cross-license their patents. The firm says the deal covers patents to be filed over the next 10 years as well as existing patents. Samsung said it also paves the way for deeper collaboration on research and development for Samsung and Google. The two already collaborate on smartphones and televisions.

Other corporate reports to watch for include earnings from ExxonMobil, boosted by rising refinery revenues and natural gas prices. Ford and Chrysler will also announce their results this week. Both firms have been boosted by North American sales, but were hit by the deep slump in Europe.

Richard Davies Business Correspondent ABC News Radio abcnews.com Twitter: daviesnow