Lots of homework problems, homework problems

Question 1 answer: Pu Songling (1640-1715), a native of Zibo, his former residence is located in Pujiazhuang, south of Zichuan, divided into two courtyards, the main house where Pu was born, that is, named "Liao Zhai". There is a full well in the east of the village, and legend has it that Pu Shi set up tea here to entertain pedestrians, and the second question is answered:

Mirage. mirage

A strange scene that appears in the sky or below the horizon when a sharp temperature gradient causes light to be significantly refracted by light. Also known as mirage. The mirage is the abode of the legendary sea gods, and the mirage is the legendary dragon, which can "exhale for the tower", so the mirage or mirage refers to the ethereal illusion.

Mirages often occur in seaside and desert areas, as well as in polar ice fields. Upper and lower mirages are common, and sometimes there are side mirages or more complex mirages.

Upper mirages are often found in areas such as snowy fields and cold oceans. These areas are cooled near the surface, creating a dramatic temperature gradient of hot at the top and cold at the bottom. Due to the refraction of the atmosphere, the scene of the ground is lifted upwards and displayed in the air, and it seems that distant objects appear to be at a certain height in the sky, and even distant scenes below the horizon can be seen.

Mirages often occur over waters, land, seashores, and highways that are strongly warmed by the sun. The warming of the earth's surface creates a violent temperature gradient of cold at the top and hot at the bottom, so that the physical scene on the ground is refracted below the ground. This mirage is often inverted, and the scene has strong shaking.

Question 3: The density of glass is one-third smaller than that of plastic, and if you enter glass three times larger than it, I calculated that it should be one-twelve.

Assuming AB distance x, then there are two possibilities for BC distance.

1) C is between AB, then there is BC=X-2

Then there is x 10+(x-2) 6=3

It can be solved that x=2)c is outside ab, then bc=x+2

There is x 10+(x+2) 6=3

x=10

Let ab=s1 and bc=s2.

The absolute value of s1 (8+2) +s2 (8-2)=3s2-s1 is 2

Solve for s1=10, s2=12 or s1= s2=

Let the distance between two places be xkm, x (8+2)+2 (8-2)=3

The solution is x=(3-(1 3))*10=80 3

Let the ab distance be s, then.

s/（8+2） +s-2)/(8-2) =3

Solve the equation to get s=

One less condition, if you look at the less condition, it should be the position relationship of ABC3.

Do you want to translate it?

I abscent on Friday, but I got a review piece. It constructs me confused. A worksheet can be a three-case, structural structure. It needs to be analyzed. Make a catalyst built on the basis of the speaker, the set, the catalyst