Here's a look at what causes hair to turn gray and some of the factors that affect graying. Answer: The age at which you'll get your first gray hair (assuming your hair doesn't simply fall out) is largely determined by genetics.
Profits or net income generally imply total revenue minus total expenses in a given period. In accounting, revenue is often referred to as the top line due to its position on the income statement at the very top. This is to be contrasted with the bottom line which denotes net income.
Money spent or cost incurred in an organization's efforts to generate revenue, representing the cost of doing business. Expenses may be in the form of actual cash payments (such as wages and salaries), a computed expired portion (depreciation) of an asset, or an amount taken out of earnings (such as bad debts). Expenses are summarized and charged in the income statement as deductions from the income before assessing income tax. Whereas all expenses are costs, not all costs (such as those incurred in acquisition of income generating assets) are expenses.