Дано:
АВСД- трапеция
угол А= углу В=90градусов
ВС=3см
СД=4см
угол ВС=150градусов
Найти: Площадь АВСД
ПОЖАЛУСТА ПАМРГИТЕ

решите систему 

 {2х+3z=6

{3x+5z=8

Образуйте форму мн.ч Род.пад

степень окисления +4 имеет сера в соединении с 1) H2SO4 2)FeS 3) H2SO3 4) NaHSO4

Употребите глаголы,данные в скобках,в Present Perfect или Pasr Simple. 1.Jill (buy)a new car two weeks ago.2.His hair is very short.He (have) a haircut.3.Last night I (arrive)home at half past twelve.4.(You/visit) many museums when you were in Paris?.5.My bicycle isnt her any more.Somebody (take) it.6.When(you/give)up smoking?.7.I(not/eat)anything yesterday because I (not/fell) hungry.8.Why (Jim/not/want)to play tennis last Friday?9.The car looks very clean.(You/wash) it?10.Brian:Hello,Susan.I Alan here?Susan:No,I am afraid he (go out).Brian: Oh,what a pity!When exactly (he/go out)?Susan:About ten minutes ago. ПОМОГИТЕ!