A)
String weather; String precipitation; weather = "погода"; precipitation = "осадки"; Console.WriteLine(weather + " выше нуля, "+ precipitation+" нет"); Console.ReadLine();
b)
String homelibrary; String book; String iss; String shelf; String shelf1; String on; int a; int b; a = 1982; b = 5; homelibrary = "домашняя библиотека"; book = "книга"; iss = "находится"; shelf = "полка"; shelf1 = "полки"; on = "на"; Console.WriteLine(homelibrary + " "+book + " издана в " + " "+a + "." + " "+book + " "+iss + " ниже" + " "+b + " "+shelf1); Console.ReadLine();
3 по примеру сделаешь сам)