начертите вектор а и постройте векторы 2а

обьясните что такое ионная связь и изменение металических и не металлических свойств в периудах и главных

There are two opinions about building up weapons. Some politicians think that there are too many weapons on our planet. They say the nuclear weapons that different countries have are enough to destroy all life on Earth ten times over. The progress in science and technology makes people invent even more destructive types of weapons and this vicious circle has to be broken. 

Others contradict them and say that powerful  modern weapons guatantee peace and stability in the world as they cool of aggressive  countries and groups of people and make them think twice  before starting a military conflict.  Which of these points of view would you support? Give your arguments.

Задача, состоит в том,  привести аргументы "за" и "против" оружия. 

Заранее огромное спасибо! 

почему у современного человека подбородок более острый, чем у его предков