2015-05-26
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A new atomic clock being developed for navigation satellites will perform better than previous devices. The clock, which incorporates a hydrogen maser, will use new microwave cavity design to provide a compact and lightweight package, and new electronic techniques to maintain long-term stability. The clock can provide precise navigation information because it is stable to one second in three million years. The differences in the time when signals from four satellites arrive at one location can be used to calculate that position to within a few yards.
Задание 2. Представьте, что вы являетесь членом организации по защите окружающей среды "Green Peace ". Напишите обращение к людям, используя модальные глаголы must, needn’t, mustn’t. Вы можете использовать следующие словосочетания:
to keep your region green; to drop litter in public places; to plant trees and flowers; to care for the animals; to pollute air with gases.
ОБУЧАЮЩИЙ МОДУЛЬ 8.2
The Atom and Its Peaceful Usage
УРОВЕНЬ
Задание 1. Прочитайте и переведите тексты со словарем
