The Half-Life of a Radioactive Isotope Is 140 Days

question 62

Multiple Choice

The half-life of a radioactive isotope is 140 days.In how many days does the decay rate of a sample of this isotope decrease to one fourth its initial decay rate?

• A)35 days
• B)70 days
• C)105 days
• D)210 days
• E)280 days

---

Definitions:

Income Statement

A financial statement that shows a company's revenues and expenses over a specific period, culminating in the net profit or loss for that period.

Accounts Payable

The amounts owed by a company to suppliers or creditors for goods and services received but not yet paid for.

Inventories

Inventories consist of raw materials, work-in-progress, and finished goods held by a company during the production and sales process, awaiting sale.

Cost of Goods Sold

The direct costs attributable to the production of the goods sold by a company, including the cost of the materials and labor directly involved in creating the product.