时针和分针几点才能成直角---Previous Question Part: ...在位值图上摆出了数 121, 请你移动一片小圆片, 使这个数最 大是 (220)。 Place Value Chart Description: Type: Table representing place values. Main Elements: - Headers: 百位 (Hundreds), 十位 (Tens), 个位 (Ones) - Content: - 百位: 1 dot - 十位: 2 dots - 个位: 1 dot This represents the number 121. Section Title: 二、选择题: 把正确答案的字母填在 ( ) 里。 (Multiple Choice Questions: Fill the letter of the correct answer in the ( ).) Question 1: Stem: 1. 下列数中, 一个0都不读的数是 ( C )。 Options: A. 1008 B. 1080 C. 8100 D. 8001 Annotation: ( C ) is circled. Question 2: Stem: 2. 估算 349+502 时, 最接近精确答案的是 ( C )。 Annotations: Under 349+502, "851" is written. Options: A. 340+500 Annotation: Under 340+500, "840" is written. This option is crossed out. B. 350+510 Annotation: Under 350+510, "860" is written. C. 350+500 Annotation: Under 350+500, "850" is written. D. 300+500 Annotation: Under 300+500, "800" is written. Annotation: ( C ) is circled. Question 3: Stem: 3. 当 ( C ) 的时候, 钟面上的分针和时针所夹的角是直角。 Options: A. 10:50 Annotation: This option is crossed out. B. 3:30 Annotation: This option is crossed out. C. 19:00 Annotation: This option is underlined, and "-12" is written below it. D. 21:00 Annotation: This option is crossed out. Annotation: ( C ) is circled. The question stem and options A, B, D are crossed out with a large X. Question 4: Stem: 4. 下面说法正确的是 ( C )。 Options: A. 10克与10米一样大。 Annotation: This option is crossed out. B. 7千克的铁比7千克的棉花重。 Annotation: This option is crossed out. C. 一个三角形至少有两个角是锐角。 D. 一个正方形剪去一个角后, 剩下的图形一定是五边形。 Annotation: "五边形" is underlined and marked with an X. This option is crossed out. Annotation: ( C ) is circled.