A rectangular tank 30 cm long and 22 cm wide has a water depth of 12 cm. After a stone is placed, the water depth is 19 cm. What is the volume of the stone?

Stone volume
=30×22×（19-12）
=30×22×7
=4620 CC

When a stone is put into a rectangular flume with a length and width of 40 cm and a depth of 14 cm, the water surface rises to 17 cm. What is the volume of the stone?

The volume of stone = the volume of water rising
40×40×（17-14）
=1600×3
=4800 CC

A cuboid glass jar, measuring 28cm in length, 15cm in width and 20cm in height, has a volume of () ml

Volume = 28 × 15 × 20 = 8400 CC = 8400 ml
A cuboid glass jar is 28 cm long, 15 cm wide and 20 cm high. Its volume is (8400) ml

110 meters long and 100 meters wide

1 mu = 666.67 square meters, so this land = 110 * 100 / 666.67 = 16.5 mu

Given a ^ x = 2 and a ^ y = 3, it is faster to find the values of a ^ 2x + 3Y and a ^ 3x + 2Y

a^(2x+3y)=a^2x*a^3y
=(a^x)²*（a^y）³
=2²*3³
=4*27
=108
A ^ 3x + 2Y the final result is as follows:
2³*3²=8*9=72

Happy English words

1. Happiness; well being: care for the happiness of children; obtain real happiness; seek happiness; work for the well being

Xiao Li, Xiao Liu and Xiao Wang, one of them teaches Chinese, one math and one English
It is known that Xiao Li and his Chinese teacher are different ages. Xiao Liu and his Chinese teacher live in the same community. Xiao Liu and his math teacher often play chess. What subjects do the three teachers teach

Xiao Wang -- Chinese teacher
Xiao Liu, an English teacher
Xiao Li -- Mathematics Teacher

Finding the total differential of u = e ^ XYZ

It is necessary to find the partial derivatives of X, y and Z respectively
For X: YZ e ^ XYZ
For Y: XZ e ^ XYZ
For Z: XY e ^ XYZ
So Du = YZ e ^ XYZ DX + XZ e ^ XYZ dy + XY e ^ XYZ DZ

69.8 - (4.7 + 19.8), 4.74-8.98 + 15.98, 2.5-1.98, 7.2 * 9.9, 7.2 * 10.1, 88.8 * 1.25, 7 / 2.5, 2.3 / 1.25
5.6/3.5
Urgent seek

69.8-(4.7+19.8)=(69.8-19.8)-4.7=50-4.7=45.34.74-8.98+15.98=4.74+(15.98-8.98)=4.74+7=11.742.5-1.98=2.5-(2-0.02)=2.5-2+0.02=0.527.2*9.9=7.2*(10-0.1)=72-0.72=71.287.2*10.1=7.2(10.0.1)=72+0.72=72.7288.8*1...

Find 1,1-2,1-2 + 4,1-2 + 4-8 The general term formula of

Careful observation shows that,
This sequence takes the first term as 1,
The sum of the first n terms of an equal ratio sequence with a common ratio of - 2,
The first is the former,
The second is the first two,
The third is the first three,
So, the general term is an = [1 - (- 2) ^ n] / 3

A rectangular tank 30 cm long and 22 cm wide has a water depth of 12 cm. After a stone is placed, the water depth is 19 cm. What is the volume of the stone?