13. Incorrect. The answer is true not false

The test can be formulated as follows

H₀: μ=0.060

H_a: μ ≠ 0.060, so a two-tailed test is required.

Under the H₀, T=(`X- μ)(n-1)^0.5/s=(0.063-0.060)*9^0.5/0.003=3.

For a two-tailed test at 5% level of significance, the decision rule is to reject H₀ if T lies outside the interval (-t_0.995 to +t_0.995 ), which for (10-1) degrees of freedom is the interval -3.25 to 2.26. Reject H₀ otherwise. Since T=3, we reject H₀ at 5% level. The machine is therefore in the proper working conditions.