Probability and Statistics question please help

Let $X_1,X_2,...,X_n$ be a random sample with $E(X_k) = 1.5$ and $Var(X_k) = 9$. Another random sample $Y_1,Y_2,...,Y_n$ is selected, independent of the previous sample. The new sample has $E(Y_k) = 2$ and $Var(Y_k) = 4$. Both samples have sample size $n = 100$.

c) Find the value $\delta> 0$ such that: $P(| \hat{Y} − \hat{X}|< \delta) =0.95.$
d) Find the minimum value $n$ such that $P(| \hat{Y} − \hat{X}|< 0.1) ≤0.95.$