Bài 6. Một vật có khối lượng 0,5 kg được thả rơi tự do từ độ cao h so với mặt đất. Biết cơ năng của vật là 100 J. Lấy g = 10 m/s 2 . Chọn gốc thế năng tại mặt đất. a. Tính h. b. Xác định độ cao của vật mà tại đó động năng gấp ba lần thế năng. c. Khi chạm đất vật nảy lên và đạt độ cao cực đại thấp hơn h là 8 m. Hỏi tại sao có sự mất mát năng lượng? Phần năng lượng bị mất mát là bao nhiêu?

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Women leaders are handling the pandemic brilliantly. Why aren't there more of them? In Taiwan, early intervention measures have controlled the coronavirus pandemic so successfully that it is now exporting millions of face masks to help the European Union and others. Germany has overseen the largest-scale coronavirus testing program in Europe, conducting 350,000 tests each week, detecting the virus early enough to isolate and treat patients effectively. In New Zealand, the prime minister took early action to shut down tourism and impose a month-long lockdown on the entire country, limiting coronavirus casualties to just four deaths. All three places have received accolades for their impressive handling of the coronavirus pandemic. They are scattered across the globe: one is in the heart of Europe, one is in Asia and the other is in the South Pacific. But they have one thing in common: they're all led by women. The success of these and other women-led governments in dealing with a global pandemic is all the more note worthy, given that women make up less than 7% of world leaders. These countries -- all multi-party democracies with high levels of public trust in their governments -- have contained the pandemic through early, scientific intervention. They have implemented widespread testing, easy access to quality medical treatment, aggressive contact tracing and tough restrictions on social gatherings. It's too early to say definitively which leaders will emerge as having taken enough of the right steps to control the spread of coronavirus -- and save lives. But the examples above show that a disproportionately large number of leaders who acted early and decisively were women. dịch sang tiếng việt nhé nhanh lên mình đang cần gấp