The bottom radius of a cylinder is 2 cm and its height is 6 cm. Its side area is (), its surface area is (), and its volume is（ The bottom radius of a cylinder is 2 cm and its height is 6 cm. Its side area is (), its surface area is (), and its volume is ()

The bottom radius of a cylinder is 2 cm and its height is 6 cm. Its side area is (), its surface area is (), and its volume is（ The bottom radius of a cylinder is 2 cm and its height is 6 cm. Its side area is (), its surface area is (), and its volume is ()

The side area is 75.36, the surface area is 100.48, and the volume is 75.36

One second gap =? Light years =? Astronomical units =? Kilometers

One astronomical unit: the average distance between the earth and the sun is about 150 million kilometers. 149597870 kilometers astronomical unit is the basic unit for measuring distance in astronomy. In daily work and study, whenever people encounter a huge number, they often exclaim: "ah, it's an astronomical number!" indeed, Astronomy

When measuring the average speed of 100 meters for a student, the timekeeper starts to count the time when he hears the starting gun at the end. The result shows that the student's score is 10 seconds. If the speed in the air is 340m / s, ask (1) what is the average speed of the student measured in meters / seconds (2) what is the actual average speed of 100 meters

Answer: 10M / s, 68 / 7m / S

Divide a circle with a diameter of ACM into several parts, cut it apart and form an approximate rectangle with a circumference of () cm
A.2*3.14*a B.（2*3.14+1）a C.（2*3.14+2）a D.（3.14+2）a

a + 2 pi a = (1 + 2pi) a
Choose B

2004+6-8+10+12-14+16+18-20+22+24-26+28+…… +96-98+100
To use a simple algorithm,

=2004+(6-8+10)+(12-14+16)+(18-20+22)+(24-26+28)+…… +(96-98+100 ) =2004+(8+14+20+…… +98) = 2004 + [(8 + 98) x16] / 2 = = 2852 (16 items)

Function f (x) = {log2x, X ≥ 1, - 2 ^ x, X

x>=1
Then log2 (x) > = log2 (1)
That is Y > = 0
x

As shown in the picture, a rectangular grassland is 16 meters long and 10 meters wide. There are two paths in the middle. One is a rectangle and the other is a parallelogram. The area of the grassland is______ Square meters

(16-2) × (10-2) = 14 × 8 = 112 (square meters); answer: the area of grassland is 112 square meters

Fill in 2.1, 2.5, 2.9, 18.4, 18.8, 19.2, 34.7, 35.1, 35.5 in the grid to make the sum on the horizontal, vertical and oblique lines the same

2.5,35.5 ,18.4
34.7 ,18.8,2.9
19.2 ,2.1 ,35.1

Let the sequence {an} satisfy the following relation A1 = 2A (a is a constant that is not zero) an = 2A - A ^ 2 / an-1 sequence BN = 1 / (an-a), find the general term formula of {BN}

A1 = 2A, A2 = 2a-a ^ 2 / A1 = 2a-a ^ 2 / (2a) = 3A / 2A3 = 2a-a ^ 2 / (A2) = 2a-a ^ 2 / (3a / 2) = 2a-a ^ 2 / (3a / 2) = 2a-2a / 3 = 4A / 3A4 = 2a-a ^ 2 / A3 = 2a-a ^ 2 / (4a / 3) = 2a-3a / 4 = 5A / 4, it can be guessed that an = (n + 1) a / NN = 1,2,3,4 holds, let n = k s holds, that is AK = (K + 1) a / K, then when n = k + 1, a (K + 1) =

To pave the floor of a house, if you use 6-decimeter-long square bricks, you need 80 pieces. If you use 8-decimeter-long square bricks instead, how many pieces do you need?

Let's use the square brick with the side length of 8 decimeters, which needs x pieces, 8 × 8 × x = 6 × 6 × 80; & nbsp; & nbsp; & nbsp; & nbsp; 64x = 2880, & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; X = 45. A: use the square brick with the side length of 8 decimeters, which needs 45 pieces