(1) On the contour topographic map, the relatively low-lying part between the two peaks is saddle A, the contour line bulges to low altitude as ridge B, and the contour line bulges to high altitude as valley C;

(2) The altitude of the top of Jiashan Mountain is 1700m, the altitude of D is1000m, and the relative height of the two places is1700-1000m = 700m; The influence of topography on climate is mainly manifested in the decrease of temperature with the increase of topography. Generally speaking, the temperature drops by 0.6℃ for every increase of 100 m. When the difference between the two places is 700 meters, the difference is 4.2℃. Peak temperature = 2-4.2 =-2.2℃.

(3) Measure that the distance between the top of base A and base B is 3cm. According to scale = actual distance on the map, actual distance = distance scale on the map = 3 ÷150000 =150000 cm =1.5km. 。

So the answer is: (1) saddle; Ridge; Valley; (2)-2.2℃; (3) 1.5.