х - время, которое плыла лодка по течению реки
10+2=12 (км/ч) - скорость лодки по течению
10-2=8 (км/ч) - скорость лодки против течения
12*х=8*(5-х)
12х=40-8х
12х+8х=40
20х=40
х=40:20
х=2 (ч)
Ответ: 2 часа лодка плыла по течению реки
I like reading books. I love works from the genre of fantasy and adventure. My favorite book "The Golden Compass" or "Northern Lights" was written by the English writer Phillip Pulman.The plot of this book is that:
Twelve-year-old Lira goes on an amazing journey to the North Pole to save her kidnapped friend. To help the girl come the northern witches led by the beautiful Seraphina Pekkala and a huge armored bear. On their way are the sinister Mrs. Coulter and the army of her monsters.
I can not say that all books are useful. Some of them are boring and meaningless. To summarize, I must say that everyone should read books, because they make us more intelligent and wise.
1. had won
2 were you doing
3. were you carrying, was carrying , had come
A zoo is a place where various animals, reptiles, mammals, insects and birds are kept. Sometimes you can see rare species of animals there. Usually zoos don’t contain domestic or farm animals, but sometimes there are children’s areas with such creatures, as donkeys, mini-horses, sheep, geese, pigs, rabbits and even pheasants. These are secluded areas where children can pet and feed animals. A visit to the zoo can be both entertaining and educational. There we can learn new facts about animals’ lives. Due to quick urbanization and deforestation many species cannot live in their natural habitat anymore. That’s why zoos and reservations exist. Opinions on advantages and disadvantages of keeping animals in the zoos differ. Some people think that zoo is a perfect place for animals, as they are always fed, well-treated and live in good conditions there. Besides, people are happy to have a chance to see wild, beautiful and exotic animals in live, to learn more about their behavior and lifestyle. From the other hand, animals have to live as close to their natural habitat as possible, for example, near forests, rivers, savannahs, jungles, safari, etc. in this respect, open zoos or wildlife reserves are much better. They usually occupy vast expanses of land and let the animals move around instead of sitting in a cage. These areas are protected and supervised by the government.
+5•(-4)=-20 Плюс на минус даёт минус
-20+19=-1