# X and Y are two elements which form $X_2Y_3$ and $X_3Y_4$.If 0.20mol of $X_2Y_3$ weighs 32.0g and 0.4mol of $X_3Y_4$ weighs 92.8g.The atomic weights of X and Y are respectively
$\begin{array}{1 1}(a)\;\text{16.0 and 56.0}\\(b)\;\text{8.0 and 28.0} \\(c)\;\text{56.0 and 16.0}\\(d)\;\text{28.0 and 8.0}\end{array}$