Based on the situation below, determine the type of hypothesis testing case and the distribution used. a) The company that produces a calculator claims that the average lifespan of the calculator they produce is 5 years with a standard deviation of 1.9 years.) A sample of 30 calculators was selected to test the lifespan and the result shows that the average lifespan is 8 years. Assume that the lifespan of the calculator is approximately normal distribution. b) It is reported by the meteorology department that the average temperature in Melaka during hot season is at least 30 . A researcher then took (a sample data of 10 days during the hot season and found that the mean temperature was 32 with a standard deviation of 14.6.) Assume that the temperature follows a normal distribution.