Anwer each of the following questions by T (for true) or F (for false).
If you answer true you are saying that the equation is true for all values of $a$, $b$, and $c$.
If you find working with letters confusing you can test your ideas by letting $a=3$, $b=4$, and $c=5$.

i) $(a+b)+c = a+(b+c)$ is .

ii) $(a-b)-c = a-(b-c)$ is .

iii) $(a-b)+c = a-(b+c)$ is .

iv) $(a+b)-c = a+(b-c)$ is .

v) $(a\div b)\div c = a\div (b\div c)$ is .

vi) $(a\div b)\times c = a\div (b\times c)$ is .

vii) $(a\times b)\div c = a\times (b\div c)$ is .

viii) $(a\times b)\times c = a\times (b\times c)$ is .