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?