= Solution
At the conventional $5\%$ <significance level>, Student 1's <p-value> $0.72$ gives \b[no rejection of equal mean wear], while Student 2's <p-value> $0.009$ gives \b[rejection of equal mean wear]. The latter also rejects at the $1\%$ <significance level>. More generally, compare each <p-value> with the prespecified level $\alpha$; no decision threshold was fixed in the data supplied.
Failure to reject does not establish equality, and a <p-value> is not the posterior <probability> that the <null hypothesis> is true. These two-sided <p-values> alone also do not identify which material has larger <mean> wear.
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