A. Read and understand the given statements below. Determine the value of a or a/2 based on the alternative hypothesis in decimal form. Write your answer in mathematical symbol in your notebook.

1. In 2015, it was recorded that around 34% of the population in 2015 were not married. A researcher surveyed a random sample of 500 couples. He found out that 18% of them were living together but unmarried. Test at 5% significance level that the
current percentage of unmarried couples is different from 34%.
2. An average construction worker hourly rate pay in the Philippines is Php 62.50 with
a standard deviation of Php 6.01. A random sample of 20 manufacturing workers were
asked on their hourly rate and found out that they had an average of Php 50 hourly
rate pay with a standard deviation of Php 5.00. Construct a 90% confidence interval that the average hourly rate for construction workers is higher than the average hourly
rate for manufacturing workers.
3. A chemist invented an additive to increase the lifespan of rechargeable battery. The said additive will extend on average the battery's lifespan to 48 months. Test the hypothesis at 0.01 level of significance that the average lifespan is higher than 48 months.​