Calculate the height formula after growing up

Calculate the height formula after growing up

Future height is predictable
Parents are more concerned about how tall their children will grow in the future, especially their parents who are not very tall. They want to know how tall their children will grow in the future as soon as possible
Current height prediction method
At present, the height prediction method is also called Volcker's prediction method. This height prediction method uses the following formula to predict the child's future height based on the child's current height: HM = a + B × C
In the formula, HM is the height of the child as an adult, a is a fixed value, B is the coefficient of the corresponding age, and C is the height of the child at that time. Due to the differences in the world, the error is 3 cm
It has been proved that this method is basically suitable for China's national conditions. However, for early or late maturing children, the prediction value may be higher or lower
Foot length and height prediction method
Adult height = foot length at age 13 × 7
Using this method to predict children's future height is more simple and convenient, the error is less than 3 cm
Parents height prediction method
According to this principle, a European scientist has created a formula to predict the height of a child based on the relationship between the height of the parent and the height of the child
Son's height  cm =  father's height + mother's height × 1.08 △ 2
Daughter's height  cm =  father's height × 0.923 + mother's height △ 2
This formula is basically consistent with the genetic rules of "height increases height", "dwarf matches dwarf", "height increases height". This formula is based on the genetic principle and the growth rate of European height
In order to make the prediction formula more suitable for China's national conditions, Chinese scientists "make foreign things serve China". According to the relationship between the height of Han children and their parents in Central China, the coefficient in the formula is changed to 1.11-1.12 for men and 0.948-0.980 for women. In this way, the calculated results are more in line with the actual situation in China

Find the weight calculation formula of elliptical iron pipe,
100 * 160 * 6mm oval tube, length is 6m, how much weight?
Note: the inner diameter is 10 cm and 16 cm high, and the thickness is 6 mm. Please help me to calculate,

Weight calculation formula of elliptical iron pipe: side area * length * iron density
The formula for calculating the area of ellipse side π = a'b '
That is to say, the area of an ellipse is equal to the product of PI multiplied by the length (a) and the length (b) of the major half axis of the outer ring of the ellipse minus PI multiplied by the length (a ') and the length (B') of the major half axis of the inner ring of the ellipse
Side area * length * density of iron = 0.00256224 * 6 * 7860 = 120.8352384kg
The final weight is about 120 kg, 240 kg~

What's the weight of 1 meter iron pipe with a diameter of 9 cm and a wall thickness of 2 cm

Mass = volume * density
Bottom area of iron pipe = pi * [0.045 * 0.045 - (0.045-0.02) * (0.045-0.02)] = 0.0044 M2
Therefore, the volume of iron pipe is 0.0044 cubic meters
The density of iron is 7900 kg / m3
Therefore, weight = 7900 * 0.0044 = 34.76kg