Construct a confidence interval for using each random sample. Assume a normally distributed population. a) x

Construct a confidence interval for μ using each random sample. Assume a normally distributed population.
a) x̅ = 79.3, n = 12, s = 9.2, 95% confidence.
b) x̅ = 5.81, n = 20, s = 0.75, 90% confidence.
c) x̅ = 312.11, n = 5, s = 19.62, 99% confidence.
d) x̅ = 93.61, n = 50, s = 10.74, 95% confidence.