Question

Revolving doors were invented in 1888 by Theophilus Van Kannel, who wanted to solve several problems with traditional swinging doors. Regular doors constantly let cold winter air rush into buildings when opened, wasting heating energy. They also created congestion during busy times because people had to wait for others to pass through. Van Kannel's rotating design allowed continuous movement of people in both directions while keeping a barrier between inside and outside air at all times. Today, revolving doors can save buildings up to 30% on heating and cooling costs. They're especially popular in skyscrapers and hotels where hundreds of people enter and exit throughout the day.

Based on the passage, what were the main problems that revolving doors solved?

A

Doors that were too heavy and difficult to open for elderly people

B

Security concerns and the need to monitor who enters buildings

C

Energy waste from temperature loss and crowding at entrances

D

Doors that broke easily and were expensive to repair frequently

Answer 1

C

The passage states revolving doors prevent outside air from rushing in (reducing heating/cooling loss) and reduce congestion by allowing continuous movement of people.