A random sample of 270 residents of a major city were asked if they knew about the World A phone before the advertising

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A random sample of 270 residents of a major city were asked if they knew about the World A phone before the advertising campaign. In this survey 18.5% of respondents had heard of World A. After the advertising campaign a second random sample 203 residents were exactly the same question using the same protocol. In this case 39.9% of respondents has heard of the World A phone. At 5% significance level, do these results provide evidence that customer recognition decreased after the advertising campaign? The null and alternative hypotheses are