n> <span class='no'>pre_test</span>[,<span class='fl'>1</span>] + <span class='fu'>c</span>(<span class='fl'>0</span>,<span class='fl'>1</span>,<span class='fl'>1</span>,<span class='fl'>0</span>,<span class='fl'>0</span>),
             <span class='kw'>pst_item2</span> <span class='kw'>=</span> <span class='no'>pre_test</span>[,<span class='fl'>2</span>] + <span class='fu'>c</span>(<span class='fl'>0</span>,<span class='fl'>1</span>,<span class='fl'>0</span>,<span class='fl'>0</span>,<span class='fl'>1</sp