Randomly selected students were given five seconds to estimate the value of a product of numbers with the results shown below.
Estimates from students given 1×2×3×4×5×6×7×8:
800, 500, 842, 560, 25, 40320, 1110, 40320, 169, 600
Estimates from students given 8×7×6×5×4×3×2×1:
2000, 400, 500, 1500, 50000, 400, 350, 300, 52836, 3500
Use a 0.05 significance level to test the claim that the two populations have the same mean.
(a) The test statistic is