How to calculate the wood diameter of 0.70% in 4 meter cubic meter

How to calculate the wood diameter of 0.70% in 4 meter cubic meter

V=0.00007854L[D+0.5L+0.005L²+0.000125L（14-L）²（D-10）]²
It turns out that D is replaced by D = 70 in centimeters
V=1.7709m³

The diameter of the big head of a tree is 15 cm, and the height is 4 M. how many squares of wood can be calculated

The height is 400 cm and the radius is 15 / 2 = 7.5 cm
Therefore, the volume of wood is:
π * 7.5 ^ 2 * 400 = 70650 cm3 = 7.065 M3

Two pieces of wood are 6 meters long, a small head diameter of 40 cm, big head diameter of 50 cm, another small head diameter of 40 cm, big head diameter of 60 cm, which
Two pieces of wood are 6 meters long. One is 40 cm in diameter and the other is 50 cm in diameter. The other is 40 cm in diameter and 60 cm in diameter?

The wood with small head diameter of 40 cm and big head diameter of 50 cm is 0.9577 square;
The diameter of the small head is 40 cm, the diameter of the big head is 60 cm, the wood is 1.1932 square, so the second one is more, 0.2355 square