Точка b находится в середине оирезка ac. неподвижные точечные заряды 2q и -q расположены в точках а и с соответсвенно.какой заряд надо поместить в точку с взамен заряда -q,чтобы напряженность электрического поля в точке b увеличилась в 2 раза варианты ответов: 1) 2q; 2)-2q; 3) 4q; 4) -4q объясните подробно как решать данное
1. Two weeks ago I went down town to buy a birthday present for my elder sister. You couldn't meet more wonderful person than her. She is one of the most charming women I know. She is also the most generous-hearted person I've ever met. Mother says she could be a bit tidier than she is. Anyway, the present I wanted to buy her had to be the best I could afford. Eventually, I came across the most beautiful scarf I had ever seen. Imagine my disappointment when I discovered the next day that Mother had bought her exactly the came scarf.