Carolyn's net profit from her investment was $1,805.
Investment in 200 shares at $30 per share = $6,000
Loan from brokerage firm = $3,000
Annual interest rate = 5%
Interest expense for 6 months = $75 ($3,000 x 5% x 6/12)
Proceeds from the sale of the investment = $8,000 ($40 x 200)
Commission to brokerage firm = $120
The Gross profit from the sale of the investment = $2,000 ($8,000 - $6,000)
The Net profit from the investment = $1,805 ($2,000 - $75 - $120).
Thus, Carolyn's net profit from her investment was $1,805.
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