1. A recent study of 500 Americans found that 37% of those sampled plan to spend more money this holiday season than they did during the last holiday season. Using a 90% confidence level, estimate the percentage of all Americans who plan to spend more money this holiday season than they did during the last holiday season.

2. An ornithologist needs to estimate the average weight of the Allen's hummingbird. Based on previous studies, we can assume that the weights of all Allen's hummingbirds have a normal distribution with a standard deviation of 0.33 gram. Determine the sample size necessary to estimate at a 95% confidence level the mean weight of all Allen's hummingbirds with a margin of error of 0.08 grams.