A cuboid container with length of 80cm, width of 50cm and height of 30cm is filled with water. Pour the water into a goldfish tank with length of 100cm, width of 60cm and height of 35cm. (1) how long is the distance between the water surface and the tank mouth? (2) how much glass does it need to make such a goldfish tank?

A cuboid container with length of 80cm, width of 50cm and height of 30cm is filled with water. Pour the water into a goldfish tank with length of 100cm, width of 60cm and height of 35cm. (1) how long is the distance between the water surface and the tank mouth? (2) how much glass does it need to make such a goldfish tank?

(1)80*50*30=120000（cm^3）
120000/100/60=20(cm)
35-20=15(cm)
(2) The first: 80 * 50 + 80 * 30 * 2 + 30 * 50 * 2 = 11800 (cm ^ 2)
Second: 100 * 60 + 100 * 35 * 2 + 35 * 60 = 15600 (cm ^ 2)

The length, width and height of a rectangular alloy are 80cm, 60cm and 100cm respectively. Now it is to be forged into a new cuboid. Its bottom is a square with a side length of 40cm

If the cuboid volume is v = length × width × height = 80 × 60 × 100 = 480000 cubic centimeters, the height of the new cuboid is V (40 × 40) = 300cm

1. In the right triangle ABC, BD is the bisector of the angle of △ ABC, BF is the bisector of the angle of △ BDA, DF is the height of three △ BDE
If ∠ DBE = 15 ° is known, calculate the degree of ∠ A and ∠ EDF
2. In △ ABC, ad AE AF is the high, angular bisector and middle line of △ ABC
【1】 Please write out all equal angles and equal segments in the graph

1. The original question is: in the right triangle ABC, ∠ C = 90 ° BD is the bisector of the angle of △ ABC, DF is the bisector of the angle of △ BDA, De is the height of three △ BDA, and it is known that ∠ DBE = 15 ° to find the degree of ∠ a and ∠ EDF
∠DBE=15,∠ABC=2∠DBE=30
A = 90 - ABC = 90-30 = 60 degrees
∠BDA=180-∠A-∠DBE=180-60-15=105
∠BDF=1/2∠BDA=52.5
∠BDE=90-∠DBE=90-15=75
∠ EDF = 75-52.5 = 22.5 degrees
2. Equivalent line segment: BF = CF
Equal angle: ∠ ADB = ∠ ADC = 90
∠BAE=∠CAE