Analyze the income statement for LMN Inc. for the year ended December 31, 2023, to assess its profitability and cost efficiency.

LMN Inc. Income Statement	Year Ended December 31, 2023
Revenue
Sales Revenue	$800,000
Interest Income	$15,000
Total Revenue	$815,000
Expenses
Cost of Goods Sold	$300,000
Operating Expenses	$250,000
Depreciation Expense	$40,000
Interest Expense	$20,000
Income Tax Expense	$70,000
Total Expenses	$680,000
Net Income	$135,000

Questions:

1. Calculate the gross profit margin and discuss its importance in assessing the company's profitability.
2. Analyze the operating profit margin and explain how it reflects the company's operational efficiency.
3. Compute the net profit margin and discuss its significance in evaluating overall profitability.