Can anyone help me find a good question urgently to find an additional score of 30

The idiom group refers to crossing the river in the same boat in the wind and rain, which is a metaphor for getting through difficulties together. (Through thick and thin).

Refers to braving the wind and rain to travel. The poetry group is worried about the country and the people:

The mountains and rivers are broken and the wind is fluttering, and the life experience is ups and downs.

Meihua North and South Road, wind and rain wet clothes.

Who is out of the ridge with? Return to your hometown as if you don't return!

The mountains and rivers are eternal, and the city is not for a while.

Starve to death Zhenwuzhi, and pick roses in dreams.

Show a faint melancholy:

The free flying flowers are as light as a dream, and the boundless rain is as thin as sorrow.

The palace is sad to see the moon, and the night rain hears the sound of bell intestines breaking.

Xiaolou listened to the spring rain overnight, and sold apricot blossoms in the Ming Dynasty in the deep alleys.

After the rain, we believe that a large amount of rain will cause floods, this kind of natural disasters are unavoidable, and urban waterlogging is a test of the management level of a city, we can not eliminate floods, but we can do our best to minimize the damage.

1. Together.

2. Wind and rain.

3. The mountains and rivers are broken and the wind is fluttering, and the life experience is ups and downs.

4. Flying flowers are as light as a dream; The boundless rain is as thin as sorrow.

5, we believe that the rain is greater than the work, in ancient times there was Dayu to control the water to prevent floods, the existing rain floods in many places every summer, bringing economic losses and even threats to people's lives.

=100 (similar to the above question).

Hehe, hurriedly calculated. Don't know, right? The landlord refers to it himself.

I feel that the focus of this place is to use the summation formula of the difference series, you should have just learned this place

Sister is here to give you a little guidance 1) Original style.

2) The principle is the same as above.

Original = (100 + 96 + .4）+(99+95+..3)-(98+94+..2+)-97+93+..1)=100

3) Original = (2000+1998+...)2）-(1999+1997+..1)=1001*1000-1000*1000=1000

4) The simplest, direct original = 51 * (1 + 101) 2-50 * (2 + 100) 2 = 51

5) Original formula = 2002 * 2 + 2000 * 2 + .2*2=2*(2+4+..2002)=2*1001*(2+2002)/2=2004*1001=2006004

When you are familiar with the practice, you can see it at a glance upstairs

I don't have time to think! I'll tell you the answers to the other questions when I have time!!

Friend, you ask too much, wealth is too little, and no one wants to help you see so much.

1. The amount of grass growing per day is x

If there is a y in the grassland, then (y+24*x) 70*24=(y+60*x) 30*60 simplification: y=480x

Therefore, the daily growth of grass is one-480th of the original (the result cannot be calculated)4 Set A x, B y, 2x + 2y = 42; 14x=42+14y x=12 y=9

5. Teams A, B and C complete all the projects separately, and day C 1 a+1 b=1 6,1 b+1 c=1 10,1 a+1 c=1 5

Additive: 1 a+1 b+1 c=7 30

Subtraction: c = 15

b=30a=15/2

6. Each team of A, B and C needs 15, 30, 15 2 days to complete all the projects separately, and set up x square meters for the table and y square meters for the table legs.

x+y=5x*50*4=y*300

Solution: x=5-y

5-y)*200=300y

1000=500y

y=2x=3

3 square meters of table top, 2 square meters of legs.

7 seems to be wrong, only said **, not at all.

83.67 million square kilometers).

I'm tired, count it yourself, give it a point.

(1) Let x: the amount of grass eaten per cow per day Set y: the amount of grass grown per day 24 70x=1+24y: 30 60x=1+60y The joint solution yields y=slightly.

4) Let A x, B y, 2x+2y=42; 14x=42+14y ok

5) Oh, I have limited time, the questions are not difficult, they are all elementary school questions, set x, y, and joint conditions!

I'm leaving, sorry!