Answer:
$294,000
Explanation:
Data provided in the question:
Profit during the first year = $30,000
Increase in profit each year = $4,000
Now,
Profit for the current year = Profit for the previous year + $4,000
Therefore,
Year                 Current year profit
 1                           $30,000
 2                           $34,000                   [$30,000 + $4.000]
 3                           $38,000                   [$34,000 + $4.000]
 4                           $42,000                   [$38,000 + $4.000]
 5                           $46,000                   [$42,000 + $4.000]
 6                           $50,000                   [$46,000 + $4.000]
 7                           $54,000                   [$50,000 + $4.000]
Hence,
The total profit during the first 7 years of business = ∑ (Current year profit)
= $30,000 + $34,000 + $38,000 + $42,000 + $46,000 + $50,000 + $54,000
= $294,000