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sau 2 thang co :153600000dong
Chép bài nhau là bạn witch roses
Ải dải nhanh nhất có tích
2. We brush our teeth every morning and evening.
3. Who is Michael going to buy some souvenirs for?
4. Was Justin born in New York on the fifth of December?
5. Children should drink milk and fruit juices everyday.
6. Bruce was happy because he was the best player.
7. Did you sing any English songs at Linda's birthday party?
8. What Thanh Giong do when his rod was broken?
9. Do your friends watching sciences programmes on VTV3 every Friday?
10. Mrs Thompson has a lot of plants in her hourse.
( Duyệt, câu 1 là gì vậy bạn)
ai giúp tớ được không
viet cau hinh e
1s2 2s2 2p6 3s2 3p6 3d1 4s2
ta co p+n+e =34
ma P=E suy ra 2p +n =34
2p =1,833 +n
p<n<1,5p
suy ra 3p<2p+n<3,5p
3p<34<3,5p
34:3,5<p<34:3
=9,7<p<11,3
thu p=10 va 11 ta thay 11 hop li nen chon p=11=e
r la na va la nguyen to kim loai vi co 1e lop ngoai cung
r co 2 dong vi r1 va r2 .Tong so hat trong r1 la 54 hat va r2 la 52 hat Biet r1 chiem 25% va r2 chiem 75%
Tinh khoi luong nguyen tu trung binh
cho 10,4g 2 kim loai x y o 2 chu ki lien tiep thuoc nhom 2a tac dung 490,2g hcl duoc 6,72 lit khi dktc va dd A
xac dinh X Y tim thanh phan phan tram