figs wrote:If a and b are integers and 4a+b is an odd number is ((a^2)/b ) > 0?

1. (b^3 + 1) > 0
2. ab < 0

4a+b is odd tells us that b is an odd number.

1. (b^3 + 1) > 0
b^3 > -1

so b^3 is greater than -1 and b is odd. So b can't be 0 but it can be 1.

We need to know whether a=0 or some other integer to determine if ((a^2)/b ) > 0.

So 1 is Insuff

2.ab < 0

This tells us that either a or b is negative and the other is positive, but we don't know which. If a is negative then ((a^2)/b ) > 0 is true. If b is the negative then it would be false.

So insuff

Combined we know that b is the positive and a is the negative and that a does not equal 0.

So Suff

I will go with C.