(Full score: 120, time: 100 minutes)

Choose carefully (of the four options given in each question below, only one is correct. Note: There are many different ways to choose the right answer. This question 10 small question, 3 points for each small question, ***30 points)

(DrawingNo. 1)

1. As shown in the figure, the index finger and thumb of both hands are in the same plane, and the diagonal line they form can be regarded as ().

A. isomorphic angle B. internal dislocation angle C. antipodal angle D. ipsilateral internal angle

2. If the two sides of an isosceles triangle are 3 and 7 respectively, then its circumference is ().

A.12b.13c. 17d.13 or17.

3. The object piled up by four identical small cubes is shown in the figure, and its left view is ().

4. If a < b < 0, the error in the following inequality is ().

A.ab>0 B. a+b