span class="op">(</span><span class="va">di</span><span class="op">)</span><span class="op">*</span><span class="va">rk</span><span class="op">)</span></span></span>
<span class="r-in"><span><span class="va">T7</span></span></span>
<span class="r-in"><span><span class="fu"><a href="https://rdrr.io/r/stats/t.test.html" class="external-link">t.test</a></span><span class="op">(</span><span class="va">T7</span><span class="op">$</span><span class="va">srk</span>, alternative <span class="op">=</span> <span clas