ПЛИЗ ПОМОГИТЕ!   Пешеход прошёл расстояние от станции до поселка за 5 часов , а велосипедист за 2 часа. Скорость велосипедиста на 6 км/ч больше чем у пешехода, найдите скорость пешехода. (решается уравнением, только каким не догнал!) 

автомобиль начинает движение по прямой из состояния покоя с ускорением 0,2м/с в квадрате . За какое время он приобретает скорость 20м/с

Упрастите выражение:

(8-2√15)(√5+√3)²

(если что знак √ - квадратный корень)

Выражение (√5+√3) ---  В квадрате!(если невидно)

Заполните пропуски соответствующим местоимением.
 
a) something, anything, nothing, everything
 
Example: ... is all right, the patient is much better today. - Everything is all right, the patient is much better today.
 
1. ... is all right, the patient is much better today. 2. Is there... interesting in the program of the concert? 3. I could see...: it was quite dark. 4. Give me... to drink. 5.I didn't take any money with me, so I  couldn’t buy ... . 6. My new eyeglasses are very good, I can see ... now. 7. I saw... near the wood that
looked like a tent.
 
b) somebody, anybody, nobody, everybody
 
Example: Has ... in the group got a dictionary? - Has anybody in the group got a dictionary?   
 
1. Has ... in the group got a dictionary? 2. ... left a magazine in our classroom yesterday. 3. The question was so difficult that... could answer it. 4.1am afraid I shan't be able to find... in the office now: it's too
late. 5. ... knows that water is necessary for life. 6. Is there... here who knows French? 7. You must find ...who can help you. 8. ... knew anything about America before Columbus discovered it. 9.I saw... in the train yesterday who looked like you.
 
c) somewhere, anywhere, nowhere, everywhere
 
Example: Did you go ... on Sunday? - Did you go anywhere on Sunday?
 
1. Did you go ... on Sunday? 2. You must go ... in summer. 3. I put my dictionary... yesterday and now I can't find it. - Of course, that is because you leave your books ... 4.1 haven't seen him ... . 5.1 know the place is... about here, but exactly where I don't know. 6. Did you go... yesterday? - No, I

went... , I stayed at home the whole day.

точка D лежит на отрезке AB, точка С на отрезке AD; AB = 120 см, CD = 3/4 AB, AC:BD = 1:5. найдите AD