Answer:
The manufacturer's claim is not supported
Explanation:
The time duration the battery of the foldable drone is said to last, μ = 4 hours
The number of drones that were tested, n = 10 drones
The sample mean,
= 4.2 hours
The standard deviation, s = 0.4 hours
The hypothesis test level of significance = 0.5
The null hypothesis, H₀; μ = 4
The alternative hypothesis, Hₐ; μ ≠ 4
The test statistic is given as follows;

We get;

Therefore, the test statistic, t ≈ 1.58
The degrees of freedom, d. f. = n - 1
For n = 10, we have;
The degrees of freedom, d. f. = 10 - 1 = 9
From the t-table at 0.5 level of significance, the critical-t = 0.7
Given that the test statistic is larger than the critical-t, we reject the null hypothesis and there is enough statistical evidence to suggest that the manufacturer claim is not supported and that the mean is not 4 hours as claimed.