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Fifty years ago, when I began exploring the ocean, no one - not Jacques Perrin, not Jacques Cousteau or Rachel Carson - imagined that we could do anything to harm the ocean by what we put into it or by what we took out of it. It seemed, at the time, to be a sea of Eden, but now we know, and now we are facing paradise lost. I want to share with you my personal view of changes in the sea that affect all of us, and to consider why it matters that in 50 years, we've lost - actually, we've taken, we've eaten - more than 90 percent of the big fish in the sea; why you should care that nearly half of the coral reefs have disappeared; why a mysterious depletion of oxygen in large areas of the Pacific should concern not only the creatures that are dying, but it really should concern you. It does concern you, as well. I'm haunted by the thought of what Ray Anderson calls "tomorrow's child," asking why we didn't do something on our watch to save sharks and squids and coral reefs and the living ocean while there still was time. Well, now is that time. Please protect the sea, protect the environment !!!

Ca 2 nguoi 48 tuoi.

Tổng tuổi của hà và bố hà là

38+10=48(tuổi)

Đáp số:48 tuổi

Hong Kong has significantly to offer for you as a customer, if you are coming here on business and for joy Hong Kong generally includes a place for you, you could make it occur the trip to that city. Hong Kong is really a town of charm. The complexity of an international city, ethnic diversity and multicultural life style are at the key of Hong Kong's attractions. The Peak is certainly one of the most popular attractions in Hong Kong but not the sole one. The Giant Buddha, Hong Kong Disneyland Resort and Ocean Park are just a number of the beauties of Hong Kong.

 =>(x-1)/2=(-2y+4)/-6=(3z-9)/12 
=(x-1-2y+4+3z-9)/(2-6+12) 
=-16/8=-2 
=> (x-1)/2=-2<=>x-1=-4<=>x=-3 
=>(y-2)/3=-2<=>y-2=-6<=>y=-4 
=>(z-3)/4=-2<=>z-3=-8<=>z=-5

1/5 thể tích của bể = 20% thể tích của bể

Để bể đầy , bể cần có thêm số % là :

  100 - 90 = 10%

Thời gian để bể đầy là :

  1 : 2 = 0,5 [ giờ ]

0,5 giờ = 30 phút

         Đáp số : 30 phút