Read the following texts. Text one. The Introdusing yourself. My name’s Octavio and I’m from Recife in Brazil. I like playing football on the beach,

Seagulls - one of the most famous birds, because they usually are numerous beaches, rivers and lakes where people are going. Seagulls - birds with complex social organization. All year round they kept flocks and between individuals developed a complex system of communication links. Externally it is expressed in blatancy birds. Gulls carry a large load of information. A striking behavior and vociferously they draw attention to themselves. 
Dimensions gulls are very different. There are kinds of very small - with thrush, others - with goose. Mostly white plumage, but the body is generally darker milestones - from light - to bluish black head in many species of black or brown, black wing tips. Such color have only adult birds. 
Gulls feed on animal food that is produced on the water and on land. Can eat grasshoppers or beetles accompanying tractor in the fields. Some feed in certain situations of small rodents and even gophers. But mostly gulls eat by the water. Swallow food, sitting on the water or grabbing on the fly. 
Being a very lively and beautiful birds seagulls are an ornament of our nature. 

1 км = 1 000 м:

6 км 400 м = 6 * 1 000 + 400 = 6 400 м

6 км 99 м = 6 * 1 000 + 99 = 6 099м

6 400 м  > 6 099 м  или  6 км 400 м  >  6 км 99 м

1 см = 10 мм:

1 см 5 мм = 1 * 10 + 5 = 15 мм

16 мм  >  15 мм   или   16 мм  >  1 см 5 мм

1 км = 1 000 м:

7 км 800 м = 7 * 1 000 + 800 = 7 800 м

7 км 80 м = 7 * 1 000 + 80 = 7 080 м

7 800 м  >  7 080 м   или   7 км 800 м  >  7 км 80 м

1 дм = 10 см;   1 см = 10 мм;   1 дм = 100 мм:

7 дм 8 см = 7 * 100 + 8 * 10 = 780 мм

7 дм 81 мм = 7 * 100 + 81 = 781 мм

780 мм  <  781 мм   или   7 дм 8 см  <  7 дм 81 мм