Biết nguyên tử B có tổng số hạt là 21. Số hạt không mang điện chiếm 33,33%. Xác định p,e,n của nguyên tử B.

1)Viết tất cả các phương trình hóa học về TCHH của oxit bazơ. ( Viết tất cả lun nha) 2) Viết tất cả các phương trình hóa học về TCHH của oxit axit.( Viết tất cả lun nha) 3) Viết tất cả các phương trình hóa học về TCHH của axit (Viết tất cả lun nha)

Giúp mình với mình đang cần gấp

Viết phần giới thiệu bài nói về nông thân bằng tiếng anh. Dài chút nha. Mk cảm ơn

vẽ mầm lo lắng nl:định tỏ tình lần thứ 2 mà cứ sợ bị từ chối wa 💔💔💔🤡🤡 tỏ tình thất bại là thành🤡🤡🤡

101. I wish the teacher ______ us more about the exam before it takes place. A) would tell B) has told C) had told D) tells 102. I wish you _______ here now. I miss you a lot. A) are B) were C) had been D) will be 103. I wish you _______. I’m sure you would enjoy joining us. A) could come B) had come C) may come D) would come 104. She won’t help me. I wish she _______ me. A) will help B) would help C) helps D) had helped 105. I wish I _______ the last bus. Now I’ll have to walk. A) didn’t miss B) hadn’t missed C) wouldn’t miss D) wouldn’t have missed 106. Don’t you wish we _______ tonight? A) weren’t going B) aren’t going C) don’t go D) hadn’t gone 107. It is raining. I wish it _______. A) hadn’t rain B) didn’t rain C) weren’t raining D) isn’t raining 108. When it was too late, he wished he _______ a better husband. A) has been B) had been C) were D) would be 109. You can’t change things simply by wishing they _______ different. A) are B) will be C) would be D) were 110. I wish he _______ to Tokyo with me last weekend. A) came B) would come C) had come D) could come 111. I wish that you _______ such a bad headache because I’m sure that you’d have enjoyed the party. A) didn’t have B) hadn’t had C) wouldn’t have D) won’t have 112. I wish that I _______ with you last summer. A) went B) could go C) have gone D) could’ve gone 113. You might have cleaned the bath after you’d used it. I wish you _______ the bath after using it. A) had cleaned B) cleaned C) would clean D) clean 114. You might come to work a bit earlier on Mondays. I wish you _______ a bit earlier on Mondays. A) had come B) would’ve come C) were coming D) would come 115. You might have remembered my birthday. I wish you _______ my birthday. A) had remembered B) remembered C) would remember D) could remember 116. You might make less noise. If only you _______ less noise. A) had made B) made C) would make D) might make 117. If only I _____ busy yesterday. I could have helped you with the problem. A) weren’t B) hadn’t been C) wasn’t D) haven’t been 118. He wishes his father _____ him some shoes before the new term starts. A) was buying B) was going to buy C) would buy D) had bought 119. I wish our school _______ a bigger library than it has. A) had had B) would have C) had D) will have 120. I wish we _______ late for this film. I can’t follow the story. A) didn’t arrive B) hadn’t arrived C) wouldn’t arrive D) wouldn’t have arrived giúp em đi mn:(( nay nộp gấp rồiiii

tính những hằng đẳng thức đáng nhớ (x+y)^2+(x+y)^2+2(x+y)^2+2(x+y)×(x+y) tính hộ em ạ

Một con lắc lò xo thẳng đứng, khi vật ở vị trí cân bằng lò xo giãn 2,5 cm. Khi vật dao động chiều dài biến thiên từ 32cm đến 38 cm. Lấy g = 10 m/s2. Vận tốc dao động cực đại là A. 6c cm/s. B. 30 cm/s. C. 40 cm/s D. 50 cm/s.

nguyên tử trung hoà về điện là do nguyên tử có

Giúp mk gấp ạ !!!! Mk sắp muộn rồi !