Hai hợp từ của cùng 1 loài nguyên phân liên tiếp một số lần không bằng nhau, môi trường nội bào đã cung cấp nguyên liệu tương đương với 360 NST đơn. Hợp từ 2 có số lần nguyên phân gấp đôi So lân nguyên phân của hợp từ l. Ơ kỳ giữa của nguyên phân, trong mỗi tế bào có 20 NST kép. Hãy xác định:
a. Số lằn nguyên phân của mỗi hợp từ trên.
b. Số loại giao tử tối đa được tạo ra của loài.
Biết rằng trên mỗi cặp NST đều mang ít nhất 1 cặp gen dị hợp và quá trình giảm phân diễn ra bình thường.

Giải phương trinh: \(t+t^2-20=0\)

Có ý kiến cho rằng bệnh mù màu, máu khó đông là bệnh của nam giới vì bệnh chỉ xuất hiện ở người nam. Em hãy cho biết nhận định trên là đúng hay sai? Giải thích.

Các biện pháp bảo vệ rừng? Vì sao cần phải bảo về rừng?

hoa perfects to play ping pong ( would rather)
i saw linda last on new year's day(since)
I haven't seen that man here before
=>This.....................................

The first Olympic Games were held in Greece in 776 BC. (1)....... was only one event. People ran a race the length ò the (2)..... . The games (3) ....... one day. Slowly people added more (4)..... .The games only for (5)..... And women could not even watch them. Only Greeks (6)..... They came (7)..... all parts of the Greek world. The time of the games was a time of peace, and the government (8)..... everyone travel safely. Kings competed (9) ....... common people. The winners became (10)..... heroes.

Complete the letter:

Dear Nam,

1.Last week/my family/two-day trip/home village

2.We /start/the journey/very early/morning.

3.After three hours/travel/bus/we/reach/old banyan/entrance/the village.

4.Everyone/feel/tired/take a rest/the tree.

5.Afetr that/we/start/walk/the village/twenty minutes/come/my grandparents'house.

6.We/spend/enjoyable weekend/the country.

7.We/feel.happy and healthy/the trip.

fill in each blank with a suitable prepostion:

1.The Ao dai consists ........................a long silk tunic that is slit on the sides and worn over loose pants

2.The design and material used for men are different..............................those used for women.

3.What do you usually wear............................the weekend?

4.The material,called jeans,was named......................................sailors from Genoa in Italy.

5.Famous designers started making their own styles of jeans,with their own lables...........................................them.

6.However,jeans have never been..............................................of fashion.

7.Wearing uniform encourages students to be pround..........................................being students of their school.

8.I haven't seen her.................................2003.

9.I have known him..............................over six years.

10.Wearing uniform helps students feel equal .......................................................many ways

11.I think it'dd necessary..................................students to waer uniforms when thay are....................................school

12.Shall we go............................................a pinic tomorrow ?-It depends..................................the weather.

13.The Park was named............................................a young hero,Le Van Tam.

14.In the 18th century jean cloth was completely made..................................cotton.

15.Children shoes usually wear.........................very quickly.

16.The price of gold has gone ...............................by over 30%

17.Vietnamese women today often wear modern .................work,but wear AO dai.....................special occasions.

18.Are you fond ..................................wearing jeans?

Task 5. Choose one item from the list in 1. Make an outline, and then write a paragraph on one of the topics.

Cho △ ABC,góc A=90,AC=3AB,D,E thuộc AC sao cho AD=DE=EC.C/m:

a.△BDE ∼ △ CDB

b.∠AEb +∠ ACB=45