упростите выражение sin(a-П)-tg (3П-а)+cos(3П/2+а)

Найдите силу тока в стальном проводнике длиной 10м и сечением 2мм^2, на который подано напряжение 12мВ.

Помогите перевести текст грамотно.The Lion, the Witch and the Wardrobe is an amazing adventure film in the magical world of Narnia.Peter, Susan, Edmund and Lucy Pevensie go to Professor Kirke,s house. Lucy (Georgia Henley) hides in a wardrobe during a game of hide-and-seek, and she discovers the world of Narnia. She tells her brothers and sister about it and the adventure begins. The Children meet Aslan the lion and other strange creatures. But Narnia has got problems with the White Witch (Tilda Swinton). What will happen to them? The Lion, the Witch and the Wardrobe is a thrilling adventure for the whole family. Dont mess it.

Запишите уравнения реакций получения водорода конверсией водяных паров: а) с углем. б) с метаном.