What is the surface area of a regular pyramid whose vertices are on the same sphere, whose height is 3 and volume is 6

What is the surface area of a regular pyramid whose vertices are on the same sphere, whose height is 3 and volume is 6

∵ the height of a regular pyramid is 3, the volume is 6, the side length is root 6, and the radius is R (using Pythagorean theorem). First, the distance from the center of the circle to the square R - (2r-3) = 3-R (3-R) ^ 2 + 3 = R ^ 2 ∵ r = 2, and the surface area is = 4 / 3 π R ^ 2 = 16 / 3 π R ^ 2

ABCD ABC = DCDC, how much is ABCD?

It is known from the title that a, B, C and D are integers between 0 and 9,
A-D = 1, D is not equal to 0, d = 2C or D = 2c-10
So, C is not equal to 0, D is one of 2,4,6,8
The original formula can be changed to 1000A + 100b + 10C + D - (100a + 10B + C) = 1010d + 101c (formula 2)
1. If d = 2, then a = 3, C = 1, take a, B, C into formula 2, there is B

1. ABCD minus ABC equals DCDC. 2. ABCD multiplied by 4 equals DCBA

1.a=5,b=2,c=7,d=4
2.a=2,b=1,c=7,d=8