12. एक त्रिभुज की भुजाएँ क्रमशः 11 सेमी, 14
सेमी तथा 15 सेमी है। उस वर्ग की एक भुजा
ज्ञात कीजिए, जिसकी परिमिति दिए गए त्रिभुज
की परिमिति की दुगुनी है।
Answers
Answer:
nahshfififitittiti
Step-by-step explanation:
Coronaviruses were first discovered in the 1930s when an acute respiratory infection of domesticated chickens was shown to be caused by infectious bronchitis virus (IBV).[9] Arthur Schalk and MC Hawn described in 1931 a new respiratory infection of chickens in North Dakota. The infection of new-born chicks was characterized by gasping and listlessness. The mortality rate of the chicks was 40–90%.[10] In 1937, Fred Beaudette and Charles Hudson reported that they had successfully isolated and cultivated the infectious bronchitis virus which caused the disease.[11] In the 1940s, two more animal coronaviruses, mouse hepatitis virus (MHV) and transmissible gastroenteritis virus (TGEV), were isolated.[12] It was not realized at the time that these three different viruses were related.[13]
Human coronaviruses were discovered in the 1960s.[14] The earliest ones studied were from human patients with the common cold, which were later named human coronavirus 229E and human coronavirus OC43.[15] They were first imaged by Scottish virologist June Almeida at St. Thomas Hospital in London.[16] Other human coronaviruses have since been identified, including SARS-CoV in 2003, HCoV NL63 in 2004, HKU1 in 2005, MERS-CoV in 2012, and SARS-CoV-2 in 2019. Most of these have involved serious respiratory tract infections.[17][18]