A student investigated the reaction between magnesium carbonate powder and dilute nitric acid by measuring the decrease in mass of the flask and its contents as carbon dioxide gas was released. The experiment was repeated four times under identical conditions. The results are: Result 1: 1.12 g1.12\text{ g}1.12 g; Result 2: 1.15 g1.15\text{ g}1.15 g; Result 3: 0.61 g0.61\text{ g}0.61 g; Result 4: 1.18 g1.18\text{ g}1.18 g.
What is the range of the four results?
Calculate the mean decrease in mass, making sure to exclude the anomalous result.