2. Let X be a random variable with density function f(x) = 1 - |x|, |x| < 1. Then, the variance of X, Var(X), equals      (2)     .

7. Let \( Y = X_{1} + X_{2} + \dots + X_{15} \) be the sum of a random sample of size 15 from the distribution whose density function is \( f(x) = 1.5x^{2}, -1 < x < 1 \). What is the approximate value of \( P(-0.3 \leq Y \leq 1.5) \) when one uses the central limit theorem? (7) .