Запишите уравнение реакций, происходящих при крекинге эйкозана C20H42 до углеводородов бензиновой фракции

Доказать:

1)

1-cos^2t/1-sin^2t + tgt*ctgt = 1/cos^2t 

I. Complete the sentences by changing the form of the verb in brackets.
1. I'll be very angry if he ... (make) any more mistakes.
2. If you ... (leave) now, you will catch the bus.
3. Don't ... (wait) for me if I am late.
4. You will be fat if you .... (eat) chips everyday.
5. If you smoke too mueh. you ... (die).
6. If he ... (be) late we'll go without him.

запишите верное равенство и вставить пропущенные числа 38дм=....дм......см