Here are five things you must know for Wednesday, Aug. 29:

1. -- Stocks Rise but China Trade Concerns Linger

U.S. stock futures pointed to a modestly higher start for Wall Street on Wednesday, Aug. 29, as the bullish tone from this week's tentative trade agreement between the U.S. and Mexico faded into broader concern over the ongoing dispute between Washington and Beijing.

Contracts tied to the Dow Jones Industrial Average   rose 8 points, futures for the S&P 500  were up 2 points, and Nasdaq futures gained 14 points. U.S. stocks rose modestly on Tuesday, Aug. 28, and both the S&P 500 and the Nasdaq closed at record highs for the third straight session.

With the White House now focused on closing its recently announced deal with Mexico, which must be approved by Congress within 90 days of it being finalized, and bringing Canada into the fold in order to maintain an North American framework similar to NAFTA, investors now feel that a trade arrangement with China may not be reached until at least 2019. Added to that concern is the fact that China's economy is slowing, and the state-controlled commission mandated to direct its growth said Wednesday that a "bigger effort" will be needed in order to meet second-half and full-year targets.

Stocks in Asia finished mixed on Wednesday, with Japan's Nikkei 225 rising 0.15% and the Shanghai Composite Index tumbling 0.31% amid growth concerns for the world's second-largest economy.

In the U.S. on Wednesday, the economic calendar includes the second estimate for second-quarter GDP at 8:30 a.m. ET, with economists surveyed by FactSet expecting GDP to come in at a 4.1% annualized rate, unchanged from the first estimate. Also on the calendar is the Pending Home Sales Index for July at 10 a.m.

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2. -- Salesforce and Dick's Sporting Goods Report Earnings

Dick's Sporting Goods Inc. (DKS)  fell 9.3% in premarket trading after second-quarter earnings beat analysts' estimates but total sales and same-store sales missed estimates. The retailer also said it expects full-year same-store sales to fall 3% to 4%, more than consensus estimates of down 0.8%.

Salesforce.com Inc. (CRM)  is expected to report earnings after the closing bell on Wednesday.

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3. -- HPE Tops Third-Quarter Estimates

Hewlett Packard Enterprise Co. (HPE)  was up 1.5% in premarket trading after the IT hardware giant's fiscal third-quarter earnings and sales beat analysts' forecasts.

Adjusted earnings in the quarter were 44 cents a share on revenue of $7.76 billion. Analysts were looking for a profit of 37 cents a share on revenue of $7.68 billion.

The company said it expects fiscal fourth-quarter adjusted earnings of 39 cents to 44 cents a share; analysts are calling for 42 cents.

The earnings report, however, hardly puts to rest the long-term growth concerns that have swirled around the company for some time, wrote TheStreet's Eric Jhonsa. Particularly since HPE's numbers benefited from a pretty favorable macro and IT spending backdrop.

4. -- Tilray Sales Surge 95%

Tilray Inc. (TLRY)  rose 21% in premarket trading on Wednesday after the cannabis company reported that second-quarter sales surged 95.2% from a year earlier to $9.7 million and topped estimates of $9 million.

Sales were fueled by patient demand in Canada, sales to other licensed producers and growth overseas. Total kilogram equivalents sold and average selling prices rose 97% and 2.9%, respectively.

Tilray's loss in the quarter was 17 cents a share, wider than a loss of 1 cent last year. Analysts anticipated a loss of 9 cents a share. The net loss included non-cash compensation charges of $5.6 million. Tilray didn't issue an adjusted per share figure.

"We are very pleased with our strong start to 2018. Tilray is well-positioned to continue to pioneer the development of the global medical cannabis market and to become a leader in the adult-use cannabis market in Canada," said Tilray CEO Brendan Kennedy.

5. -- Amazon Plans New Video App - Report

Amazon.com Inc. (AMZN) is planning to launch a free, advertising-supported video service for users of its Fire TV streaming video devices, The Information reported, citing people familiar with the situation.

The new free service, which is being developed by Amazon's IMDB subsidiary, is tentatively called Free Dive. It is separate from Amazon's ad-free subscription Prime Video service, which has become a major rival to Netflix Inc. (NFLX) .

Amazon's ad business is growing faster than much of the rest of the company. It makes up most of the "other" segment in Amazon's earnings statements, rising 132% to $2.2 billion in the second quarter, The Information noted.

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