Please help me with these. Thank you.

\f1. In a time motion study, it was found out that the time required by workers to complete a certain manual operation was normally distributed with a mean of 26.6 minutes with a standard deviation of 3 minutes. A group of 25 workers was randomly selected to receive a special training for two weeks. After the training, it was found that their average time to finish the operation was 23 minutes. Can it be concluded that the special training speeds up the operation? Use 0.05 level of significance.2. An insurance company claims that the mean cost to process a claim is $60. An industry comparison showed this amount to be larger than most other insurance companies, so the company instituted cost-cutting measures. To evaluate the effect of the cost-cutting measures, the supervisor selected a random sample of 26 claims processed last month and recorded the cost to process each claim. The sample information is reported below (in $). 45 49 62 40 43 61 48 53 67 63 78 64 48 54 51 56 63 69 58 51 58 59 56 57 38 76 At the 0.05 significance level, is it reasonable to conclude that the mean cost to process a claim is now less than $60?3. A new papaya soap manufacturer claims that 80% of women who used the soap observed skin whitening within two weeks. One of their competitors makes a random survey if the claim is true. The survey results in 6 out of 10 women observed skin whitening within two weeks. With a=5%, is the soap manufacturer's claim true