Which phrase describes an unknown or changeable quantity?

• A. 4 quarts in a gallon
• B. 2 o'clock in the afternoon
• C. 3 feet 7 inches
• D. The height of the building times 1/2

1 answer

The phrase that describes an unknown or changeable quantity is:

D. The height of the building times 1/2

This expression implies that the height of the building is not specified and can vary, making it a variable quantity.