A tyre manufacturer conducts quality assurance checks on the tyres that it manufactures. One of the tests consists of undertaking a test on their medium-quality tyres with an independent random sample of 12 tyres providing a sample mean and standard deviation of 14,500 km and 800 km respectively. Given that the historical average is 15,000 km and that the population is normally distributed, test whether the sample would raise a cause for concern.