If a, b, c are consecutive positive integers and a<b<c, which of the following must be true?
I. c-a=2
II. a-c is positive integer
III. (a+b+c)/3 is an integer	Choose one:
A) I
B) II
C) I and III
D) II and III
E) I, II and III
If a, b, c are consequitive positive integers and a&lt;b&lt;c, which of the following must be true?   1. c-a=2   2. abc is an even integer   3. (a+b+c) /3 is an integer   1.   a=a   b=a+1   c=a+2   c-a=a+2-a=2.   Correct   2. a-c is negative because a&lt;c - false   3. (a+b+c) /3 is an integer   Again;   a=a   b=a+1   c=a+2   a+b+c=(a+a+1+a+2)=3a+3   3a is always divisible by 3   3 is divisible by 3.   Thus3a+3is also divisible by 3.   Rule:   if integer x is divisible by n   and   integer y is divisible by n   then; x+y must be divisible by n   Correct.   Ans :I and III( + +1+ +2)= 
<gadget id="calculator">( + +1+ +2)</gadget>
<output>3</output>
3a+3   3a is always divisible by 3   3 is divisible by 3.   Thus3a+3is also divisible by 3.   Rule:   if integer x is divisible by n   and   integer y is divisible by n   then; x+y must be divisible by n   Correct.   Ans :I and III
<result>C</result>
If a, b, c are consecutive positive integers and a<b<c, which of the following must be true?
I. c-a=2
II. a-c is positive integer
III. (a+b+c)/3 is an integer