A World Health Organisation researcher claims that the average Yemeni is 3.5kg underweight, compared to the ideal weight, due to Yemen's civil war crisis. A random sample of 25 Yemeni was weighed to test this claim, and the difference between their actual weight and their ideal weight was measured. The weight differences (in kg) measurements data are sorted below. Where appropriate, use the 5% level of significance.

a) Based on the information given, write down the null and alternative hypotheses that would help to determine if the results of the experiment support the researcher's claim.

b) Write down the name of the test you are going to use.

c) Write down the decision rule.

d) Paste the output from R Commander.

e) Do you reject or not reject the null hypothesis? Explain your answer.

f) Draw a conclusion which answers the original problem.

g) State and check all the assumptions for the hypothesis test you have used.

Weight-difference 6.3 -6.8 -0.2 -5.6 2 -3.8 4.8 -6.9 3.4 0.6 3.1 -4.4 -7.9 0.3 -8.8 -11.1 -0.5 -4.8 3.6 -0.7 2.5 -3 -1.7 0.7 -4.9