нужно вставить such a\an либо such

2) we found lovely cafe on the way home. it serves

delicious food.

3) they’re having good time.

4) my sister always gives me useful advice.

5) he’s happy person. i’ve never seen him being sad.

6) she studied at prestigious university.

7) it was sunny day. the children enjoyed playing in the

lake.

8) joan is reading interesting book.

9) oh, this is nice present. thank you.

1) the reality show was so interesting. ( it was such an interesting

show. пример)

2) anton’s father is such an intelligent person. (anton’s father is

so intelligent. пример)

3) my new job is so interesting. i have such

.

4) she’s such a pretty girl. she’s so

.

5) the test was so difficult. it was such

.

6) you had such a good idea. your idea was so

.

7) jibek’s dress is so beautiful. jibek has got such

.

8) they’ve got such expensive cars. their cars are so

.

1. We need to decide how to celebrate your birthday,

2 You needn't to go to the shop. I have bought everything we need.

3. Pupils must wear uniforms at school. It's a rule!

4. They don't have to cook dinner. Mother has done it.

5. People mustn't cross the street when traffic lights are red!

6. You have to do morning exercises! It's very useful!

7. May I take your pen? I have lost my pen

8. My friend can't speak English, but he speaks French.

9. You shouldn't go out if you feel not very well.

10. I should to take my umbrella, it's raining

Объяснение:

the side surface of this pyramid consists of 6 isosceles triangles with a base 16 and a side 17.

Find the area of one triangle.

S = 1/2bh, where b is the base and h is the height.

The height is found by the Pythagorean theorem.

The height is equal to the square root of the difference between the squares of the side of the triangle and the half of the base. Half of the base 16 / 2 = 8

17*17 - 8*8 = 225. The square root of 225 is 15. The height of the triangle is 15. Then the area of the triangle will be equal to S = 1/2*16*15 = 120 and the area of the side surface of this pyramid is equal to the area of one triangle multiplied by 6. S1 = 120 * 6 = 720