Variance scales by the square

Let X and Y be independent random variables with X ~ N(2, 4) and Y ~ N(−4, 9) where $N(\mu ,{\sigma }^2)$ denotes a normal distribution with mean $\mu$ and variance ${\sigma }^2$. Given $\Phi (1)=0.8413,\Phi (2)=0.9772$ and $\Phi (3)=0.9987$ where $\Phi (\cdot )$ is the cumulative distribution function of a standard normal random variable. Which of the following statements are true?