Một người gánh một vật nặng 14kg ở phía sau lưng. Biết rằng đòn gánh dài 1,2m. Để tay của người này chỉ phải dùng một lực 100N để giữ đòn gánh thăng bằng thì vật nặng phải được đặt cách vai một khoảng bằng bao nhiêu? Giúp mình với nha!

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III. Put the verbs in brackets into the past simple or the present perfect. 1. A: (you/ ever/ meet) anyone famous? B: Yes, last summer I (sit) next to Brad Pit on a plane to LA. 2. A: How long ago (you/ start) painting? B: Ten years ago. I (recently/ complete) a painting that the National Gallery (ask) me to do a year ago. 3. A: Last night, I (see) the latest James Bond film. B: Oh, I (already/ see) it twice. 4. A: Do you know that Mrs Janet (work) here for sixteen years? B: I thought she (start) working here ten years ago. III. Put the verbs in brackets into the correct verb form. 1. I (have)___________ dinner when his friend called. 2. Joan (travel)____________ around the world. 3. We (not begin)__________ to study for the test yet. 4. Don’t get on a bus while it (run) ______________ . 5. I (invite)______________ them to my birthday party yesterday, however, they (not come) . 6. Look! Somebody (clean)___________ the room. 7. My brother (begin)____________ looking for a job in January. 8. Timson (make) ____________________ 13 films and I think her latest is the best. 9. She (cook)______________ at the moment. That’s why she can’t answer the phone. 10. She doesn’t mind (go)______________ out in the evening. 11. I (not see)____________ him since we (leave)________ school. 12. Football (be)____________________ my favourite sport. I like (play)_________ it in my free time. 13. Jane (leave)________________ just a few minutes ago. 14. She (be) ________________ extremely quiet since her husband died.