Answer:
Test is Left tailed test
Parameter tested is standard deviation
Step-by-step explanation:
We are given the hypothesis as;
Null hypothesis; H0: σ = 8.6
Alternative hypothesis; H1: σ < 8.6
Where;σ is a constant generally known in statistics as the standard deviation.
Now, it's the alternative hypothesis that will let us know whether this is left tailed, right tailed or two tailed.
Alternative hypothesis says σ < 8.6.
This means that the values of σ that satisfy this hypothesis are less than 8.6 and thus are on the left hand side of 8.6 on a number line. Thus, the shaded region in a normal distribution curve will be on the left.
Thus, it's a left tailed test
