English composition on the weekend Please use about 60 words to describe your most impressive weekend 1: How are you doing? 2: What did you do? 3: With whom?

I had my happiest weekend whith my family.
It was a funny day.In the early morning,my father took us to the seaside by his car.We swam and went surfing.We had a great barbecue with some friends who we met there.I thought I had never enjoyed better sunshine in my entire life that afternoon.My mother and my brother went fishing and had a lot of fun.We returned home at sunset.Although we were tired,we enjoyed this weekend so much.

My mother's weekend English composition about 60 times

My mother does housework at the weekend.She gets up at 6.30a.m.After she gets up,she brushes teeth and washes face.Then she cooks breakfast for us.She cleans the house and watch TV in the morning.She ...

What is off form calculation

In the calculation of mixed operation, it is usually to calculate a formula step by step (the equal sign can not be written on the original formula), and write the process of each step. For example: 25 + 65 + 98 = 90 + 98 = 188 http:...

The resistance of a small bulb is 10 Ω, and the normal working voltage is 2.5V. Can you connect the small bulb directly to 3V power supply?
The resistance of a small bulb is 10 Ω, and the normal working voltage is 2.5V
Can you connect this small bulb directly to the 3V power supply?

For this problem, the rated current is equal to 0.25A. If it is directly connected to 3V voltage, I = 0.3A is greater than 0.25A, so it can't be directly connected. If it has to be connected to 3V voltage

It is known that the value of square-4 of fraction-4 (a + 2) / A is a positive integer, and the value of a is obtained
Trouble will do, wise man, help

Is it to find the value of integer a?
Otherwise, there are infinitely many
-4(a+2)/(a^2-4)
=-4(a+2)/[(a+2)(a-2)]
=-4/(a-2)
In this step, there is a condition that cannot be ignored, that is, a + 2 ≠ 0, a ≠ - 2
Value is a positive integer, then:
a-2=-1,a=1
a-2=-2,a=0
A-2 = - 4, a = - 2 (rounding off)
So the value of a is a = 0, a = 1

Calculation of atmospheric pressure
The diameter of the pressure cooker is 24cm, the diameter of the pressure limiting port is 2mm, and the mass of the pressure limiting valve is 100g. What is the maximum air pressure in the pressure cooker when it is used? What is the minimum pressure that should be borne by the connection between the lid and the centralized port?

Relationship between atmospheric pressure and boiling point
[example 3] (2005 Jiangxi senior high school entrance examination curriculum reform volume) the diameter of the pressure cooker is 24cm, the diameter of the pressure limiting gas port is 3.5mm, and the mass of the pressure limiting valve is 100g. What is the maximum pressure difference between the inside and outside of the pressure cooker when it is used? What is the standard atmospheric pressure? How much pressure should the interface between the lid and the cooker bear at least?
Analysis: let the pressure in the pot be, and the atmospheric pressure be. When the pressure limiting valve is just lifted and ejected outward, the gas outlet of the pressure limiting valve is affected by three forces, as shown in the figure, which are (downward), (downward) and (upward). According to the equilibrium conditions of the forces, the three forces should be met, and the maximum pressure difference between the inside and outside of the pot is, so there is standard atmospheric pressure
The minimum force that the joint between the pot cover and the pot should bear
Answer: 1 standard atmospheric pressure
Commentary: pressure cooker is a kind of closed heating container. When it is heated, the temperature of the gas sealed in the cooker rises and the pressure gradually increases. In order to limit the air pressure in the cooker to a certain range, a pressure limiting valve is installed. When the air pressure in the cooker reaches the limit value, the pressure limiting valve is lifted by the high pressure gas to release part of the gas and reduce the pressure of the gas in the cooker to ensure safety, The maximum pressure difference between the inside and outside of the pot in this question is the difference between the inside and outside of the pot when the gas in the pot just lifts the pressure limiting valve; the minimum pressure that the interface between the pot cover and the pot can bear is actually equal to the difference between the inside and outside pressure on the pot cover

There is only one common point between the straight line passing P (0, - 1) and the hyperbola x ^ 2-y ^ 2 / 3 = 1

There is only one common point between the straight line passing P (0, - 1) and the hyperbola x ^ 2-y ^ 2 / 3 = 1,
(1) If there is only one intersection point, then the straight line is parallel to the hyperbolic asymptote
Hyperbolic asymptote y = ± √ 3x
So the linear equation is y = ± √ 3x-1
(2) Tangency
Let the equation be y = kx-1
simultaneous
3x^2-y^2=3
y=kx-1
XiaOy de
3x^2-(k^2x^2-2kx+1)-3=0
(3-k^2)x^2+2kx-4=0
Discriminant = 4K ^ 2 + 16 (3-K ^ 2) = 0
k^2=4
k=±2
Tangent equation: y = ± 2x-1

220 V AC, a 100 K ohm resistor and a LED lamp in series, what is the voltage of LED?
How much voltage is there on the two feet of LED bulb? How to calculate it?

The lamp bead is not the same, the voltage is not the same, according to the 3V tube voltage drop calculation, the LED voltage should be 0-3v

How to write 2x / 9-x05 + 1 / x-3-x05 + 6x + 9

2x/(9-x²)+1/(x-3)-1/(x²+6x+9)=-2x/(x-3)(x+3)+(x+3)/(x-3)(x+3)-1/(x²+6x+9)=(-2x+x+3)/(x-3)(x+3)-1/(x²+6x+9)=(3-x)/(x-3)(x+3)-1/(x+3)²=-1/(x+3)-1/(x+3)²=(-x-3-1)/(x+3)²...

Each of the five houses has a 36 watt energy-saving lamp. From 6 p.m. to 6 a.m., how much electricity does it consume (a 1000 degree lamp consumes 1 degree per hour)

Both of you upstairs are wrong!
In fact, you buy 36W energy-saving lamp, the actual power is less than 20W!
I am engaged in energy-saving lamp procurement for many years!
So: 5 rooms x 20W x 12h = 1200wh = 1.2kwh = 1.2 kWh

English composition on the weekend Please use about 60 words to describe your most impressive weekend 1: How are you doing? 2: What did you do? 3: With whom?