твір на тему роль дружби в житті людини

Вобщем,мне нужно получить одно вещество из другого,например: CaO + X = CaCo3(возможно + еще что-то) Также CaCO3 + X = CaO(возможно + еще что-то) Ну и CaCl2 + X = Ca(OH)2

You have 30 minutes to do this task.

You have received a letter from your English-speaking pen-friend, Paul.

… I have to prepare a presentation about a famous scientist. The choice is

wide but I have no idea yet whom to choose…

…Which scientist do you think I can write about? What is he or she famous

for? What branch of science do you find the most interesting and why?

Write him a letter and answer his 3 questions.

Ask him 3 questions about his studies in general and his free time.

Write about 140 words. Remember the rules of letter writing.
PLEASE HELP ME!!!

приведите уравнение 2-го порядка к каноническому ввиду: -9x^2+y^2+18x-6y-9=0

Помогите пожалуйста разберите по составу слова: Собираются колышет ленивое