Question $23(1$ point$)$

On March $1,$ Sam invested $$90000$ in a business. On June $1,$ he invested another $$10000.$ On July $1,$ he withdrew $$17000$ to spend on the repair of his house. On September $1,$ he injected another $$2000$ into the business. What was his average investment per month in the business during the year? Assume all months have the same length or weighting.

$$73000$

$$37000$

$$47000$

$$77000$