Simplify: `a^6 div a^2`
(a)`a^4`
(b)`a^6`
(c)`a^2`
(d)`a^0`

Simplify: (6^(0)div 7^0)xx(8^(0)-7^(0))

Simplify: (a^(-1) +b^(-1)) div (a^(-2)-b^(-2))

Simplify: (a+b)^^2(a-b)^^2(a^(^^)2-ab+b^(^^)2)(a^(^^)2+ab+b^(^^)2)(a^(^^)4+a^(^^)2b^(^^)2+b^(^^)4)(a^(^^)6+b^(^^)6)^(^^)2'

Simplify: 4""5/6-2""2/3

Simplify 12.05 xx 5.4 div 0.6