упростите выражение: -3(4 – 2х) + 7(х - 2).

вычислите дисперсию чисел 8;7;9;11;5

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на новый год встретились шестеро друзей,Каждый пожал всем руки,и каждый подарил всем другим по подарку. а)сколько было подарков? б)сколько было рукопожатий? Решите пожалуйста

ПОМОГИТЕ !!!!!!!!!!!! СРОЧНО!!!!!!!!!!!! БУДУ ВАМ ОЧЕНЬ БЛАГОДАРEН!!!!!!!!!! Choose the right answer.
1. I...get up very early day. I live near the school .
a.mustn/t    b.don/t have to c.     won/t have to
2.My mother is .... school teachher. a.a b.the c.-(nothing)
3.Look at the man ... is stahding in the corner.
a.who  b.which c.where
4.We need ... tomatoes . I/m going to the shop.
a.some b.any c.few
5.He is very popular and has .... friends .
a.many b.much c.a lot of
6.Everybody in our class ...... English .
a.like b.likes c.will likes
7.My parents don`t know......about Star Wars
a) nothing b) everything c) anything
8. Kate has a problem. Let ... talk to me about it
a) her b) him c) me
9.Last year our family ... to the sea.
a) went b) go c) is going
10.Who ... you do your homework yesterday?
a) helps b) helped c) help

Найдите площадь треугольника abc, если угол a =30 гр. а высоты проведенные из вершин b и с, соответственно равны 5 и 8.Пожалуйста ребятки помогите)

1)Where ... the children

a)am  b)is  c)are

2)John ... got a grey rabbit 

a)have  b)has

3)My little sister doesn't  ... a bike.

a) have  b) has

4)Ann ... her beautiful  flowers  every day.

a)water   b)waters

5)Does Tiny ... letters and postcards?

a)get   b)gets

6)When do the friends ... to bed?

a)go   b)goes