I) Two separate filling units, Unit 1 and Unit 2, are used to fill jars with coffee. An experiment was then carried out, in which the quantities of coffee in some randomly selected jars filled by each of these units, were measured. The measurements are summarized in the table below.

	Sample size	Sample mean	Sample standard deviation
Jar filling unit 1	37	22.15	2.00
Jar filling unit 2	36	23.15	2.10

1. Use an appropriate hypothesis test to determine whether there is a difference between the mean quantities of coffee in jars from these two units. State clearly the hypothese, the, the test statistic and its distribution under the null hypothesis, and carry out the test at twi appropriate significance levels. Comment on your findings.

2. State clearly any assumptions you made in (I) part 1

3. Repeat the procedure in (I) part 1 to determine whether the mean quantity of coffee in jars of Unit 1 is lower than that of Unit 2.