Read the following case and answer the questions given below:
Riya stands in front of a large cliff and shouts. She hears the reflected sound after a short delay. Her teacher explains that a distinct echo can be heard only when the reflected sound reaches the ear after a sufficient time interval. The speed of sound in air is approximately \(340\ m/s\).
1. Which property of the cliff makes it suitable for producing a clear reflection of Riya's shout?
2. A science teacher explains that sound reflection can be controlled in an auditorium but deliberately used in SONAR and echolocation. Which statement best explains this difference?