Here are five things you must know for Tuesday, Sept. 18:

1. -- Stocks Rise After Trump Slaps $200 Billion More Tariffs on China

U.S. stock futures posted gains on Tuesday, Sept. 18, and global stocks firmed even after the White House slapped a levy of 10% on $200 billion worth of China-made goods.

Donald Trump said the move was aimed at drawing China to the negotiating table, but warned that tariffs on a further $267 billion worth of goods, including many consumer technology products currently exempted from the list that will kick in on Sept. 24, would be imposed if China was to react to with tariffs on U.S. imports.

"We have been very clear about the type of changes that need to be made, and we have given China every opportunity to treat us more fairly," Trump said. "But, so far, China has been unwilling to change its practices."

"If China takes retaliatory action against our farmers or other industries, we will immediately pursue phase three, which is tariffs on approximately $267 billion of additional imports," he said.

China said it was left with "no choice but to retaliate simultaneously," with the Commerce Ministry adding that it "hopes the United States would recognize the negative consequences of its actions, and take convincing steps to correct its behavior in a timely manner."

Contracts tied to the Dow Jones Industrial Average  rose 53 points, futures for the S&P 500  gained 6 points, and Nasdaq futures rose 21.75 points.

The economic calendar in the U.S. on Tuesday includes the Housing Market Index for September at 10 a.m. ET.

General Mills Inc. (GIS)  posted fiscal first-quarter profit of 71 cents a share, 7 cents ahead of estimates. Sales of $4.09 billion missed estimates of $4.12 billion. 

AutoZone Inc. (AZO)  reported fiscal fourth-quarter adjusted earnings of $18.54 a share, beating estimates of $17.99. But total sales in the period and same-store sales came in below estimates. 

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2. -- Oracle's Cloud Revenue Comes Up Short

Oracle Corp. (ORCL)  fell 3.9% in premarket trading on Tuesday after the software giant's fiscal first-quarter earnings topped expectations but revenue for cloud services did not.

Adjusted earnings in the quarter were 71 cents a share, beating forecasts by 3 cents. Total revenue was $9.19 billion, and cloud revenue was $6.61 billion. Analysts had forecast revenue of $9.24 billion and cloud services revenue of $6.68 billion.

On a conference call following the release of the earnings on Monday, co-CEO Safra Catz guided for fiscal second-quarter revenue to be flat to up 2% annually in constant currency. With Catz indicating forex is currently a 2% headwind to revenue growth, the outlook suggested revenue will be flat to down 2% in dollars, which is below a consensus for 1.6% growth. Earnings guidance of 78 cents to 80 cents a share compared with analysts' estimates of 79 cents.

Oracle maintained its forecast for revenue growth on a constant-currency basis in fiscal 2019 to be higher than the 3% growth in fiscal 2018.

3. -- Google's Android to Power Media for Renault-Nissan Alliance

Alphabet Inc.'s (GOOGL) Google entered a partnership with the Renault-Nissan-Mitsubishi Alliance that would use the tech giant's Android operating system to power next-generation intelligent infotainment systems.

Under the technology partnership, vehicles sold by the auto alliance will use Android to offer customers a new array of services including Google Maps, the Google Assistant and the Google Play Store, the companies said in a statement.  

The alliance, which last year sold a combined 10.6 million vehicles in 200 markets, will debut the new system in 2021.

The alliance's executives said many of its customers already prefer using Google's apps over the ones developed by the car companies and their suppliers. And these executives have grown comfortable with Google, which began open-sourcing its software in 2007, The Wall Street Journal reported.

"The trust was built in the last few years," said Kal Mos, the alliance's vice president of connected vehicles, in an interview with the Journal.

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4. -- Amazon to Release 8 New Alexa Devices - Report Inc. (AMZN)  plans to release at least eight new Alexa-powered devices before the end of the year, according to CNBC.

The devices include such items as a microwave oven, an amplifier, a receiver, a subwoofer, and an in-car gadget, people familiar with the matter told CNBC. All of the devices will be Alexa-enabled, while some of the devices also will have the voice assistant built in.

The products mark Amazon's first move into the home appliances space.

Amazon is expected to reveal some of the devices at an event later in September, CNBC said, citing an internal document describing the plans.

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5. -- FedEx Slumps After a Big Earnings Miss

FedEx Corp. (FDX)  slumped 2.8% in after-hours trading on Monday after reporting adjusted earnings in its fiscal first quarter of $3.46 a share, missing estimates of $3.80, while revenue of $17.1 billion beat expectations of $16.9 billion.

The shipping and logistics company said it expects adjusted earnings in fiscal 2019 of $15.85 to $16.45 a share, higher than prior guidance of adjusted earnings between $15.65 and $16.25.

The company noted that it "recognized substantially higher variable compensation accruals during the (first) quarter" and "accelerated wage increases for certain hourly employees due to the enactment of the [Tax Cuts and Jobs Act]," which negatively affected year-over-year results by $170 million.

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