Ask for the answer to the second question, hurry, hurry! There s a bounty, what s the reward!

Chaohu Lake (Chaohu Lake): Nature's magic has made Chaohu Lake the "land of fish and rice" in Jiangbei, and the smoke and clouds of history have endowed her with a wealth of scenic spots and historic sites, and it is the fifth largest freshwater lake in China.

Alchemy Lake (Anqing): 1,100 meters above sea level, it is comparable to Tianshan Tianchi and Changbai Mountain Tianchi among China's famous mountains.

Shitang Lake (Anqing): Shitang Lake has an area of more than 11 square kilometers and is known as the "Ten Mile Long Lake".

Taiping Lake (Huangshan): one of the key scenic spots in southern Anhui tourist area.

Huating Lake (Anqing): Huating Lake Scenic Area is divided into six scenic spots: Huating Lake, Longshan, Haihui Temple, Xifeng Temple, Fotu Temple, and Lion Rock.

Jiaogang Lake (Huainan): rippling blue waves, 18 rivers converge, like a heaven-sent jasper, 10,000 acres of reeds, 1,000 acres of lotus lake.

Tianjing Lake (Tongling): There are wells in the lake, the name is Tianjing, and the lake is named after the well. Qishu Lake (Huangshan): The scenery is beautiful, and it is now planning to develop a number of water tourism activities such as yachting, boating, and fishing.

Yingzhou West Lake (Fuyang): Together with Hangzhou West Lake and Huizhou West Lake, it is known as the three major West Lakes in China, and it has now been damaged.

Anhui has famous lakes such as West Lake, Taiping Lake, and Chaohu Lake.

There is a famous lake in Anhui called Chaohu Lake.

Get rid of the last lake.

Anhui has the famous Sun Lake and other lakes.

Analysis The productivity of the business tax applicable to the tourism industry is 5%, and if the tourism enterprise organizes a tour group to travel within the territory of China, the balance of the tourism fee collected minus the room fee, meal fee, transportation, ticket and other payment expenses paid to other units on behalf of the tourist is the turnover. In this question, the business tax payable by the travel agency = (3000-1200-400-950-50) 30 5% = 600 yuan.

What is the tax rate? What is this title? Mathematics?

11.There is only one movable pulley.

So f=1 3x(700+50)=250(n) the object rises at a height of 15x1 3=5(m).

Box = mg = 40x10 = 400 (n).

g (box + pulley) = 250 1 2 = 500 (n) g pulley = g (box + pulley) - g box = 500-400 = 100 (n) l pull = 2 1 2 = 4 (m).

v pull = 4 10 =

Solution: (2) Small problem, use polar coordinate transformation. Let x= cos and y= sin , then 2 1, (cos +sin ) 1, 1 (cos +sin ) 1,0 2.

Primitive = (0, 2)d [1 (cos +sin ),1)] cos +sin ) d 2= (0, 2)(cos +sin -1)d = (sin -cos - 丨( =0, 2)=2- 2.

FYI.