Please do me a favor! Give me the answer

As the name suggests, non-renewable resources are no longer available after they are used up, or they need to be regenerated for a long time, such as oil and coal, which take hundreds of millions of years to regenerate.

The concept of renewable resources can also be divided into two types:

1. Natural regeneration.

2. Regenerate it through reprocessing.

However, no matter how much regeneration is carried out, the above two regeneration methods cannot meet the needs of human life and production today. The only way out for humanity is to exploit new resources.

West. South.

Southwest. South. Southeast. North.

Northwest. West.

1. 15/2 2. 400 3. 20 4. 8,15 5. 1 6. 5：4 7. 8.The fan-shaped celery finch is 9 years old2 Give the ruler.

60 a pants potato (one (one (10 + one Kai pure key.

72x55=72x(50+5)=3600+360=3960

One (one by one, staring at 3=4.)

45 degrees, unchanged is still 45 degrees, very simple, set the angle BAD is a90-a+1 2(90-180+2a)=45It's okay with ab=ac, I'm afraid you can't understand it, talk about the idea, dae=dac+caeFormula 1, dac=bac-bad=90-a

Equation 2, CAE = 1 2 BCA = 1 2 (90-ABC) ABC = 180-2A

ABC substitution formula 2.

Equation 3, cae=1 2 (90-180+2a) Equation 1 plus equation 3 to get the equation I listed above.

...Okay, help you, dear.

First of all, push out the box above 6 and fill in 6, and you can get the multiplication of 6 is only 1 6 and 2 3. First analyze the first 1 6, when 6 is the last of the above three digits, 1 is the mantissa of the two digits, to get the following 5 to get the first digit of the three-digit number is 5, to get 4 to get the first digit of the two-digit number is 4, then the number calculated is no longer right, 4 When the upper three digits, the result is a four-digit number, not a three-digit number, so it is not right. When 6 is below and 1 is above, you can't get the answer 5, so the first way is not feasible.

The second kind of 2 3, when 2 is below and 3 is above, to get 5 then the first digit of the three-digit number must be 2 (the maximum is 2 9, only 1 can be entered), and to get 4 then the first digit of the two-digit number can only be 8 (3 8 24) At this time, it can be seen that this answer is not correct, 8 2? 3 gives a set of four digits, so no, then there is only one possibility left, that is, 3 is below 2 is above, to get the result of 5 then the first of the three digits can only be 1 (2 3 6), then 3 ? ＞20，？

To 7. Then there are two possibilities for 4, the number above 2 2 and 2 can be 3 or 4, to make 3, then the number above 4 should be 6, and the result is only 9, 39 274 + 7 is equal to 11, but when the middle number of the three-digit number is 3, the first digit of the two-digit number should be 7, but the four-digit number of 192 7 calculated in this way does not meet the requirements. Then we can conclude that the space above 9 is 4, you can analyze it yourself, the method is the same, I don't want to write, the final result is 172 23