A. Features and applications
B. Display and data connection
C. Online stores
D. Differences from iPhone
E. Business usage
F. Operating system
Paragraph 3 ______

A. Caffeine blocks production of the enzyme that stops melatonin production.
B. Caffeine interrupts the flow of the hormone that prevents people from sleeping.
C. Caffeine halves the body’s levels of sleep hormone.
D. Caffeine stays in the body for many hours.

A. it protects him against the harmful rays from space
B. it provides sufficient light for plant growth
C. it supplies the heat necessary for human survival
D. it screens off the falling meteors