Consider two identically distributed zero-mean random variables $U$ and $V.$ Let the cumulative distribution functions of $U$ and $2V$ be $F(x)$ and $G(x)$ respectively. Then, for all values of $x$
1. $F(x) - G(x) \leq 0$
2. $F(x) - G(x) \geq 0$
3. $(F(x) - G(x)) \cdot x\leq 0$
4. $(F(x) - G(x)) \cdot x\geq 0$