There are four types of sentences:- 1) Assertive: It is of two type- i) affirmative(this sentence is always positive this sentence do not include words like any, anyone) and ii)negative (which uses words...
Integer (Z)= ...-3,-2,-1,0,1,2 3,4... A.If you add two integers you will get ineger Like 4 + 5 = 9 Integer+integer=integer So , you can say integers are closed under addition....