How many times of its surface area and volume?

How many times of its surface area and volume?

Let the edge length of cube be a
Then the area is a * a * 6 = the second power of 6A
The volume is a * a * a = a to the third power
If the edge length is three times larger, the surface area is 3A * 3A * 6 = the second power of 54a
Volume = (3a) * (3a) * (3a) = the third power of 27a
In comparison, its surface area is 9 times larger and its volume is 27 times larger

The edge length of a cube increases five times, and its surface area increases______ Volume expansion______ ．

If the edge length of a cube is expanded 5 times, the surface area will be expanded 5 × 5 = 25 times, and the volume will be expanded 5 × 5 × 5 = 125 times

The edge length of the cube is three times larger, and the volume of the cube is () times larger
A. 3B. 6C. 9D. 27

According to the volume calculation method of cube and the change law of factor and product, if the edge length of a cube is increased by 3 times, its volume will be increased by 27 times

There are nine steps in front of the children's Palace Square, each of which is 8 meters long, 0.4 meters wide and 0.2 meters high. How many square meters of floor tiles should be laid on these steps

(8 * 0.4 + 8 * 0.2) * 9 = 43.2 (M2)
(L * W + L * h) * number of steps
The length * width is the surface of the step, and the length * height is the elevation of the step

As shown in the picture, the 3M long ladder leans against the wall, and the bottom of the ladder is 0.6m away from the bottom of the wall. How many meters is the top of the ladder from the ground? In the above question, if the top of the ladder slides 0.9m away from the wall, is the bottom of the ladder sliding 0.9m away from the ground? Please explain the reason

It is a right triangle, the square of 3 - the square of 0.6 = 6 / 5 times the root 6

The following is a cross-section of a staircase. The width and height of each step of 8m are 20cm. What is the cross-sectional area of this building

A total of 2.8/0.2 steps = 14 steps, the cross-sectional area of stairs is the area of a large isosceles right triangle plus 14 small isosceles right triangles, that is, 2.8x2.8x1/2 + 0.2x0.2x1/2x14 = 4.2 (square meters)

A porter carries a 500N cargo on his shoulder and climbs to the warehouse on the third floor along the stairs from the bottom of the building. If each staircase has 15 steps, each step is 20cm high
A porter carries a weight of 500N goods on his shoulder and ascends the warehouse on the third floor along the stairs from the bottom of the building. If there are 15 steps on each floor and each step is 20cm high, the porter's contribution to the goods is that the potential energy of the goods is also increased.

The steps from the first floor to the third floor are on the first floor and the second floor, not the third floor
s=15×2×0.2=6m,F=G=500N
W=FS=500×6=3000J
A: the work of moving goods is 3000j

Calf's weight is 500N. Go up the stairs to the classroom on the third floor. If there are 15 steps on each floor, and each step is 20cm high, ask calf to go up three floors from the ground
-How much work does the calf need to do to get to the third floor from the ground?

W=Fxs=900Nx（20x15x3/100）=4500

The horizontal length of the stairs in the experimental building of a school is 9m, and the gradient of the stairs is 30 degrees. If the height of each step is 20cm, how many steps should be built at least?

X + 9 = (2x)
X = 3 is radical 3
Multiply 100 by 20
Round up to 26 steps

As shown in the figure, carpet should be laid on the stair surface with a height of 3 meters and a slope of 1:2.5, and the length of carpet should be at least 3 meters______ Rice

Moving the horizontal part of each step down to AC and the vertical part right to BC, we can find that the required carpet length is AC + BC ∵ slope = BCAC = 1:2.5, BC = 3, ∵ AC = 3 × 2.5m = 7.5m, ∵ AC + BC = 10.5m, so the answer is 10.5