Direction: Select the segment of the sentence that contains the grammatical…

Solution: The segment "were required to" is incorrect.

Key point: Subject-verb agreement requires the verb to match the subject in number (singular or plural).

Rule: When a quantity or measurement is considered a single amount, use a singular verb.

• Corrected sentence: Five gallons of oil was required to get the refinery running.

• Example (singular with quantity): Two miles is a long walk.

• Example (plural when items are considered individually): Two dollars were scattered on the table.

Note: If the speaker thinks of the parts as separate individual items rather than one total amount, a plural verb can be used; here the intended meaning treats the quantity as a single amount, so use the singular verb "was."