Trong không gian với hệ tọa độ Oxyz, cho mặt phẳng ( α ): 4x+2y-6z+5=0. Khi đó một vectơ pháp tuyến của mặt phẳng là 

A. (2;1;-3)

B. (4;-2;-6)

C. (4;-2;6)

D. (4;2;6)

"Every morning from Monday to Saturday, I get up at 6 o'clock. After breakfast, I go to school by bicycle. It takes me about 20 minutes from my house to get to my school. Usually, I study at school until 11:30 a.m. I return home at noon to have lunch with my family. In the afternoon I attend English and computer classes. I always get home just in time for dinner at 7:30 p.m." 

Childhood we always live in my love me.Voi my mother loved and respected nhat.Me care raised my sister because my father always working away.
On that day in class I felt a headache, the nausea nao.Toi cold air to try to go on foot to the door nha.Moi day I called, "Mommy" and ran on foot to find the door this me.Hom I unsteadiness pale.
Mother saw me so I immediately rushed to though very tired, but I still see her mother's face pale lips trembling: "my son how this child?" She helped me into bed.
Mother blanket for me rub oil all over her hot toi.Doi warm soft hands for warmth as I do I subtract felt something rubbing his head lanh.Vua mother laments voice said: "Suffering beings, was sick to walk again "hot ginger water bowls finished .Uong sweetened see people really light then I fell asleep. Suddenly I heard her call: "My son went up to eat a bowl of hot porridge" I was watching carefully this .Luc me.Guong hearted round her face had the faint traces, but no loss of gentle beauty woman standing tuoi.Doi new mother cuddling eyes how, in his eyes full of anxiety and filled with sweet love thuong.Me deceived me like I was a kid lovely mother lam.Cai mouth blowing chao.Toi light spoons my mother suddenly saw the most beautiful mother in the soul toi.Ca traces, both eyes dark circles ... all are beautiful.
Oh! my mother, the mother had suffered hardships and worries strenuous cared for con.Me is wonderful mother, children need mothers side. When happy and sad moments like nay.Con ailing mother loved most in the world, Mom!

Hình nào sau đây không phải là hình đa diện?

A. Hình trụ

B. Hình tứ diện

C. Hình lập phương

D. Hình chóp