Перевод ненужен определите время (настоящее простое и т. 1. simple two-way radios, called walkie-talkies, have been popular children’s toys for years. 2. wireless communications systems use devices called transmitters to generate radio waves. 3. early transceivers were very large, but they have decreased in size due to advances in technology. 4. by 1995 the number of companies offered cell phones services had grown to over 1500 companies. 5. the transmitters change, or modulate, the radio waves. 6. police, fire, and other emergency departments use two-way radio to communicate information between vehicles that are already responding to emergency calls, which saves valuable time.