At the insistence of a government inspector. a new safety device is installed in an assembly line operation. After the installation of this device ' a random sample of 8 days output gave the following results for numbers of finshed components produced : 618 660 638 625 571 598 639 582. Management is concerned about the variability of daily output and views as undesirable any variance about 500 . Test at the 5% significance level the null hypothesis that the population variance for daily output does not exceed 500.