срочно помогите пожалуйста.

Sn=2n^2+3n. найти 12 член арифметической прогрессии

My older brother has got a new hobby-he has became a mountain biker. I know that mountain biking is a dangerous  kind of sport and i worry about him.I would like him to spend more time at home. I wish he had chosen a safer entertainment...

Докажите или опровергните данное высказывание "Человек любящий и умеющий читать - счастливый человек.