Help with summer homework, summer homework help

Do your own thing

Hehe, it looks familiar. It seems to be from high school.

1) How can I take all the baht and use it like mud and sand? so that the pillars of the negative building are more than the farmers of the south acre.

There are 4 "of" in the first distance, not 2.

Is there anything wrong with the question?

Child, I read it, the above questions are very simple, not difficult at all. Adjust yourself well, do one a day, and finish it at the beginning of school.

Playing, of course, is a very enjoyable thing, so why don't we think of doing these problems as a game? Play hands-on, play thinking, play travel ......What a summer vacation!

1. Demonstration experiment of electromagnetic wave propagation:

Experiment 1 Put a mobile ** into a sealed plastic bag, put it in water, and hit the mobile **. Experiments have shown that mobile ** is able to receive signals. Description: Electromagnetic waves can propagate in liquids.

Experiment 2 Put a mobile ** in a closed wooden (or iron) box, call, move** can receive a signal. Description: Electromagnetic waves can propagate in solids.

Experiment 3 Put a mobile ** in a vacuum hood, call, move ** to receive a signal. Description: Electromagnetic waves can propagate in a vacuum.

Second, the characteristics of electromagnetic waves:

a.Electromagnetic waves propagate in all directions in space;

b.No medium is required for the propagation of electromagnetic waves. But electromagnetic waves can propagate in air, water, certain solids;

c.The propagation speed of electromagnetic waves is equal to the speed of light, and the propagation speed in air and in a vacuum is similar;

d.Electromagnetic waves of different frequencies (or different wavelengths) travel at the same speed, so the shorter the wavelength of electromagnetic waves, the higher the frequency; Conversely, the frequency is lower.

I hope it helps you, and if you have any questions, you can ask them

I wish you progress in your studies and go to the next level! (*

A rectangular flower bed with a circumference of 17 meters, 1 and a half meters longer than the width, how many meters long and how wide are they? (Column).

Solution: If the width is x, then the length is x+

2(x+x+

x = 5 meters long and 5 meters wide.

As required, make the two numbers filled in as co-primes.

Prime numbers ( ) and composite numbers ( ) Prime numbers ( ) and prime numbers ( ) Odd numbers ( ) and odd numbers ( ).

Odd ( ) and even ( ) composite ( ) and composite ( ).

There is a fraction of the numerator, and the sum of the denominator is 80, which is about seven-ninths after the fraction. What is this score? (Column!) ）

Solution: If the original numerator is x, then the denominator is 80-x

x/（80-x）=7/9

x = 35 The original fraction is 35 45

A canteen brought in a total of 62 bags of flour and rice, one-fifth of the number of flour bags was two bags less than a quarter of the number of rice bags. How many bags of flour and rice are delivered? (Column!)

Solution: Set flour x bags, then rice 62-x

From the meaning of the title, we can get x 5+2=(62-x) 4

In the end, we get x=30

30 bags of flour and 32 bags of rice.

There are a total of 20 questions in a mathematics competition, and the scoring criteria are: 5 points for each correct question, and 1 point for each wrong or no question. Xiaohua participated in this competition and scored 64 points, how many questions did Xiaohua get right? (Column!)

Solution: If you do x correctly, you will get 20-x wrong, and you can see from the question 5x-(20-x)=64

The final solution is x =14

The numerator of a false fraction is 55, and after it is transformed into a fraction, the integer part, the numerator, and the denominator are 3 consecutive natural numbers. Find this with a fraction. (can be columned).

A, B, and C regularly go to an Internet café to check information, A goes once every 6 days, B goes every 8 days, and C goes every 9 days. If all three of them were in an Internet café on April 15, when and what is the next time they will meet in an Internet café? (can be columned).

Take the least common multiple of 3 people, that is, the least common multiple of 6 8 9, we can get 72, that is to say, you can meet again on the 72nd day after April 15, and May is 31 days, 72-15-31=26, then the next time you meet is June 26.

Brain teaser: Xiao Ming knows the answer to the test paper, why do you ask why you frequently peek at others?

How many eggs can a person eat on an empty stomach?

What can be used to solve all the mysteries?

How much is 8 divided into 2 halves?

Melon field plum under the original source tacit (find out the name of the poet).

Li Qingzhao said heroically and majesticly.

Hao) Yan (Zhuang) language.

Write two simplest true scores that are greater than one-sixth and less than three-quarters. They are ().

1 4 1 3 5 12 1 2 7 12 2 3 3 3 4 5 6 11 12 Choose any 2.

I'll answer the language. Li Qingzhao.

Hao) Yan (Zhuang) language.

1. If the width is x, the length is x+1

x+x+1) *2 = 17

x= The length is:

The numerator and denominator are each multiplied by the same number.

2 ——14/18 14+18=32……Not true * 3 - 21 27 21 + 27 = 48 ......Not true * 4 - 28 36 28 + 36 = 64 ......Not true * 5 - 35 45 35 + 45 = 80 ......Founded so as: 35 45

4. Let the integer part be x, then the numerator is x+1 and the denominator is x+3.

then x [(x+1) (x+2)]=55 (x+2)x=urgent.

As required, make the two numbers filled in as co-primes.

Prime numbers (2) and composite numbers (4); prime numbers (2) and prime numbers (3); odd (1) and odd (3);

odd (1) and even (2); Composite (4) and (6);

Brain teaser:

1. Xiao Ming knows the answer to the test paper, why does he frequently peek at others?

Because Xiao Ming is a teacher, check whether the questions made by the classmates are correct or not.

2. How many eggs can a person eat on an empty stomach?

One, eat one and eat again is not an empty stomach.

3. What can be used to solve all the mysteries?

Use the "Mystery" to solve all the mysteries.

4. How much is it to divide 8 into 2 halves?

It's 0, and if you cut it in half horizontally, it becomes 2 zeros.

The first one: let the length be x, the width be y, 2(x+y)=17;x-y= joint solution of two formulas, y= x=5

Third: let the denominator be a, the numerator is b, a+b=80; b a=7 9 joint solution two-formula, a=45 b=35

Fourth: let the surface be x, the meter be y, x+y=80;y 4-x 5=2 joint solution of two formulas, x= y=

7 (3-(-3) 7) Because two subtractions are additions.

To go to the elite, everyone can be an honor student.