14. A company uses cement-mixing trucks to deliver loads of concrete to job sites.
An empty cement-mixing truck welghs 26,000 pounds. Concrete weighs 4,000 pounds per cubic yard. The cement-mixing truck weighs 64,000 pounds when filled with concrete. The compound inequality shown below describes all the possible amounts of concrete (c), in cubic yards, that can be carried by the cement-mixing truck.

26,000 ≤ 4,000 + 26,000 ≤ 64,000