Xiaoming went to Huanggang Mountain, the first peak in East China (located in Wuyishan) in the summer vacation. The tour guide reminded everyone to bring an extra dress and introduced the local mounta

Xiaoming went to Huanggang Mountain, the first peak in East China (located in Wuyishan) in the summer vacation. The tour guide reminded everyone to bring an extra dress and introduced the local mountains. Solution: Solution: (1) As shown in the figure:

(2) conjecture: the functional relationship between y and x may be a linear function.

Solution: Let the function expression be: y=kx+b, and (400,28.6), (500,28.0).

Substituting y=kx+b, we get: 400k+b=28.6500k+b=28.0.

Solution: k=-0.006, b=3 1.

The functional relationship between y and x may be y=-0.006x+3 1.

When x=600, y =-0.006× 600+31= 27.1.

When x=700, y=-0.006×700+3 1=26.8.

∴ Points (600, 27.4) and (700, 26.8) are on the image of the function y=-0.006x+3 1

The functional relationship between y and x is y=-0.006x+3 1.

(3) When y= 18. 1, there is-0.006x+31=18.1.

X=2 150 (m)

Huanggang Mountain is about 2150m above sea level.