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A hot - water faucet can fill a bathtub in 20 minutes; and the cold-water faucet can fill it in 10 minutes. How long will it take to fill the same bathtub with both faucets running?

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Each of the four sides of a swimming pool measures 9 meters. the pool is 5 meters deep. how much water will be needed to fill it completely? a. 45 cubic meters b. 81 cubic meters c. 225 cubic meters d. 405 cubic meters reset next

Do social recommendations increase ad effectiveness? a study of online video viewers compared viewers who arrived at an advertising video for a particular brand by following a social media recommendation link to viewers who arrived at the same video by web browsing. data were collected on whether the viewer could correctly recall the brand being advertised after seeing the video. the results are given below.correctly recalled the brandarrival 409153browsing20484b. conduct the hypothesis test, using the 0.025 level of significance.what is the value of the test statistic? χ2stat=what is the p-value? p-value=is this value significant atα=0.025?

Find the domain of the following expression: 1/(√x)-2