$1)$ An employee participating in a defined benefit flat benefit pension plan has a benefit entitlement of $$120.$ Calculate the pension adjustment for this employee.

$2)$ Cheng is paid a monthly commission of $7\mathrm{.}5\%$ on the value of the companys goods sold. The company provides him with a mid$-$month advance of $$2000$ on the $15$th of every month. In September he sold $$123,350$ of goods. Calculate his September $30$ commission payment.