A Radioactive Material Initially Is Observed to Have an Activity

question 1

Multiple Choice

A radioactive material initially is observed to have an activity of 1000 decays/sec.If nine hours later it is observed to have an activity of 125 decays/s,what is its half-life?

• A) 1/2 hour
• B) 8 hours
• C) 3 hours
• D) 1 hour

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Definitions:

90-Day Note

A short-term debt obligation that is due for repayment within 90 days of the note's issuance.

Direct Write-Off Method

A method of accounting for bad debts that involves charging unpaid customer accounts directly to the income statement when they are determined to be uncollectible.

Accounting Equation

The fundamental equation that ensures the balance of a company's financial records: Assets = Liabilities + Equity.

Uncollectible Accounts

Accounts that are considered to be uncollectable due to the debtor being unlikely to pay, also known as bad debt.