How to convert kg to MPa

These two units are not the same, can not be converted. Kg is the unit of weight, MPa is the unit of pressure

How to convert pressure MPa to kilogram

Strictly speaking, MPa is the unit of pressure and kilogram is the unit of mass. Generally, it refers to all pressures per square meter, 1MPa = 1 * 1000000pa, 1pA = 1 Newton / square meter, 1kg pressure = 1 kg * 9.8 Newton / square meter
Let's convert the rest by ourselves

1: 3 is the cement mortar protective layer mass ratio or volume ratio
Such as the title

The traditional building mortar (as plastering) is volume ratio. In recent years, it is emphasized that the strength of plastering mortar should have an index, so the weight ratio must be adopted. However, the expression of mix proportion should be 179 per M; the weight ratio of materials (including water) contained in mortar is right. Therefore, 1:3 cement mortar is still the traditional expression volume ratio

A person was born in an even number of years in the 1980s. If the year of his birth cannot be written as the difference between two squares, how old will he be in 2012,

Possible year of birth: 1980, 1982, 1984, 1986, 1988
The difference between a number and two square numbers can be expressed as: x = a ^ 2-B ^ 2 = (a + b) * (a-b), where a and B are natural numbers,
From the parity of natural numbers, we can see that the two factors (a + b) and (a-b) must have the same parity (both odd or even at the same time), otherwise the number cannot be written as the difference between two square numbers
Because: 1980 = 2 * 990; 1982 = 2 * 991; 1984 = 2 * 992; 1986 = 2 * 993; 1988 = 2 * 994
So: 1982, 1986
In 1986, when he was born in 1986, he was at least 26 years old in 2012

The passenger car and the freight car leave from station a and B at the same time, and meet 5 hours later. After meeting, the two cars still move at the original speed. When they are 196 km apart, the freight car runs 80% of the whole journey. The ratio of the distance that the passenger car has traveled to the distance that it has not traveled is 3:2

196 (80% + 33 + 2-1), = 196 (45 + 35-1), = 196 (25), = 196 × 52, = 98 × 5, = 490 (km); a: the distance between a and B is 490 km

As shown in the figure, AC and BD are diagonals of quadrilateral ABCD. Try to compare the size relationship between ab + AD + BC + CD and AC + BD

Let AC and BD intersect o
Because in △ abd, AB + ad > BD (the sum of two sides in a triangle is greater than the third side)
In △ BCD, BC + CD > BD (the sum of two sides in a triangle is greater than the third side)
So AB + AD + BC + CD > 2bd,
Similarly: ab + BC + CD + ad > 2Ac
SO 2 (AB + BC + CD + DA) > 2 (AC + BD)
That is ab + BC + CD + Da > AC + BD,
In △ ABO, OA + ob > AB (the sum of two sides in a triangle is greater than the third side)
Similarly, OB + OC > BC,
OC+OD>CD,
OD+OA>AD
SO 2 (OA + ob + OC + OD) > AB + BC + CD + da
AC + BD > (AB + BC + CD + DA)
So (AB + BC + CD + DA) / 2

When 72% of the coal is used up, 18 tons of coal is put in. At this time, it is 8% more than the original. How many tons?

Set the original x tons
[x(1-72%)+18-x]/x=8%
-0.72x+18=0.08x
18=0.8x
X = 22.5 tons

A problem of mean inequality
The real number x.y satisfies 4 ^ x + 4 ^ y = 2 ^ (x + 1) + 2 ^ (y + 1). U = 2 ^ x + 2 ^ y, find the value range of U

For convenience, let 2 ^ x = A and 2 ^ y = B
u=a+b
4^x+4^y=2^(x+1)+2^(y+1)
a^2+b^2=2*a+2*b=2u
Using mean inequality
(a+b)^2≤2(a^2+b^2)
u^2≤2*2u
u^2-4u≤0
0≤u≤4

The distance between port a and port B is 1200 km. Ship a sails from port a to port B at 60 km per hour. 30 minutes after the departure of ship a, ship B sails from port B to port a at 70 km per hour. How many hours after the departure of ship B?

30 minutes = 12 hours, (1200-60 × 12) △ 60 + 70, = 1170 △ 130, = 9 hours, a: the ship B will meet 9 hours after departure

Is the square of 2x + x-3 > 0 solution set (- 3 / 2,1)
Is the solution set of the square of x-6x + 9 ≥ 0 (- ∞, 3) U (3, ∞)
Is my answer wrong? If wrong, please advise me

The second error is that the solution set is (- ∞, ∞) and the result should be (x-3) ^ 2, which is positive
The first one is also wrong
It should be a (- ∞, 1) ∪ (3 / 2, ∞) parabola with upward direction. If it is greater than zero, it should take the left and right parts of zero

How to convert kg to MPa