Nguyên nhân nào dẫn đến rừng xích đạo xanh quanh năm phát triển ở đồng bằng A-ma-dôn?

Write one word  in each gap.

Lucky accidents

Sometimes,  scientists know what they(1) __________ looking for and they find  it.  At  other

times, things(2) __________ discovered by  accident. Two  famous examples of  this are gravity and  penicillin.

Isaac Newton,(3) __________ first used  maths to  describe gravity,  was sitting (4) __________ his garden when  he  saw(5) __________ apple fall - some  say it  fell  on  his head! This made him think  about why,  and  he  realised  he (6) __________ explain  it  using  maths.

Alexander  Fleming discovered  penicillin, (7) __________ was the  first antibiotic.  It  completely

changed  medicine.  He  was  working (8) __________ his laboratory when  he  saw that  something (9) __________ started growing on  one of  his  experiments.  He  analysed  it  and  realised that  it (10) __________ be  very  useful  in  fighting disease.  Sometimes luck can be  a big help!

_Xét △ABC ta có:

        \(\widehat{A}\) + \(\widehat{B}\) + \(\widehat{C}\) = 180^o

=> 50^o + \(\widehat{B}\) + \(\widehat{C}\) = 180^o

=> \(\widehat{B}\) + \(\widehat{C}\) = 180^o \(-\) 50^o

=> \(\widehat{B}\) + \(\widehat{C}\) = 130^o : 2 = 65^o

=> \(\widehat{B}\) = \(\widehat{C}\) = 65^o

=> \(\widehat{A}\) < \(\widehat{B}\) => BC < AB

Vậy trong △ABC có:

         BC < AB

_Xét △OMN ta có:

ON = 3cm, MN = 5cm

ON = 4cm

=> OM < ON < MN => \(\widehat{N}\) < \(\widehat{M}\) < \(\widehat{O}\)

Vậy trong △OMN ta có:

                \(\widehat{N}\) < \(\widehat{M}\) < \(\widehat{O}\)