Tại sao khi sản xuất chế phẩm virus trừ sâu ngươi ta phải nuôi sâu giống, trong khi đó điều này không có ở chế phẩm nấm và chế phẩm vi khuẩn trừ sâu

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Khi sản xuất chế phẩm virus trừ sâu người ta phải nuôi sâu giống, trong khi đó điều này không có ở chế phẩm nấm và chế phẩm vi khuẩn trừ sâu vì :

+ Người ta chế ra chế phẩm virus trừ sâu bằng cách gây nhiễm virus đa diện trên sâu non. Sâu non dễ bị nhiễm virus nên người ta cần phải nuôi sâu hàng loạt. 

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Mark the letter A, B, e,or D to indicate the underlined part that needs correction in each of the following questions. ( sửa lỗi luôn ạ) 51. A lot of people think that marriage women shouldn't pursue a career. A B C D 52. We must stop discrimination on people coming from the rural area. A B C D 53. My brother is good with cooking and he can cook very delicious food. A B C D 54. I guess they may be kept home doing housework and look after their chifdren, A B C D 55. Women in rural areas might be forced to work both at home but on the fields. A B C D 56. Some people think that girls shouldn't be allowed to going to university. A B C D 57. Gender discrimination should be eliminated for create equal opportunities in educationfor everyone. A B C D 58. More girls should being chosen to represent us in the School Youth Union .. A B C D 59. Both women and men should be given equal rights for education and employment. A B C D 60. This discrimination against women and girls must be abolishing. A B C D 61. Efforts should be make to offer all children equal access to education. A B C D 62. It is clear that gender differences cannot prevent a person to pursue a job. A B C D 63. Traditional women were mainly responsible to doing housework and looking after their husbands and A B C D children. 64. Doing houseworkevery day is really boring and tired. A B C D 65. In the past, women was often passive and dependent on their husbands. A B C D 66. Women usually get less pay as men for doing the same job. A B C D

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