Exhibit 9-4

question 91

Multiple Choice

Exhibit 9-4.A school teacher is worried that the concentration of dangerous,cancer-causing radon gas in her classroom is greater than the safe level of 4pCi/L.The school samples the air for 36 days and finds an average concentration of 4.4pCi/L with a standard deviation of 1pCi/L. Refer to Exhibit 9-4.At a 5% significance level,the decision is to ___________.

• A)Reject we can conclude that the mean concentration of radon gas is greater than the safe level
• B)Reject H₀;we cannot conclude that the mean concentration of radon gas is greater than the safe level
• C)Do not reject H₀;we can conclude that the mean concentration of radon gas is greater than the safe level
• D)Do not reject H₀;we cannot conclude that the mean concentration of radon gas is greater than the safe level

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Definitions:

Accounts Payable

An accounting term for the amount of money a company owes to its suppliers or creditors for goods or services received but not yet paid for.

Accounts Receivable

Funds that customers owe to a business for products or services already received but not yet compensated for.

Cash Collections

The process of managing and collecting payments from customers for goods or services provided, crucial for maintaining a company’s liquidity.

Industrial Gas

Gases produced for use in industrial processes, such as oxygen for steel-making or nitrogen and argon for welding.