payment following the time indicated; and $($d$)$ the principal repaid by the payment following the time indicated for finding the outstanding principal.

$\backslash$table$[[$Debt Principal,$\backslash$table$[[$Repayment$],[$Period$]],\backslash$table$[[$Payment$],[$Interval$]],$Interest Rate,$\backslash$table$[[$Conversion$],[$Period$]],\backslash$table$[[$Outstanding$],[$Principal After:$]]],[$$$18,000,8$ years,$6$ months,$7\%,$semi$-$annually,$7$ th payment$]]$

$($a$)$ The size of the periodic payment is $

$($Round the final answer to the nearest cent as needed. Round all intermediate values to six decimal places as needed.$)$