1. A and B measure the length of the same object with two scales. The result measured by a is 6.50dm, and that measured by B is 0.648m A. The graduation value of the scale used by two people is the same. B. The graduation value of the scale used by two people is different. C. one of the two results must be wrong D. A's reading is more accurate than B's 2. When measuring the length of an object with a smaller scale, the measured value is compared with the real value () A. The measured value is greater than the real value B. the measured value is less than the real value C. the measured value is equal to the real value D. it cannot be judged 3. When we ring the ancient bell, we will find that after stopping the impact on the bell, the bell's "lingering sound" does not stop. The main reason is () A. The echo of the bell B. the big clock is still vibrating C. the big clock stops vibrating D. people's hearing is prolonged 4. What's the reason why people can speak? What's the reason why people can hear? 5. When playing guitar, the finger moves back and forth on the string to change the pitch by changing (). This research method uses the () method

1. A and B measure the length of the same object with two scales. The result measured by a is 6.50dm, and that measured by B is 0.648m A. The graduation value of the scale used by two people is the same. B. The graduation value of the scale used by two people is different. C. one of the two results must be wrong D. A's reading is more accurate than B's 2. When measuring the length of an object with a smaller scale, the measured value is compared with the real value () A. The measured value is greater than the real value B. the measured value is less than the real value C. the measured value is equal to the real value D. it cannot be judged 3. When we ring the ancient bell, we will find that after stopping the impact on the bell, the bell's "lingering sound" does not stop. The main reason is () A. The echo of the bell B. the big clock is still vibrating C. the big clock stops vibrating D. people's hearing is prolonged 4. What's the reason why people can speak? What's the reason why people can hear? 5. When playing guitar, the finger moves back and forth on the string to change the pitch by changing (). This research method uses the () method

B
A
B
Vocal cord vibration eardrum vibration
The length of the string (the last one depends on the corresponding chapter of the book. There are many ways)