KöMaL 2023 K760

Triangle $A(2;4)$, $B(6;4)$, $C(4;10)$ is reflected (in succession) in the line $x = a$, and then in the line $y = 2$. $a)$ What is the sum of the second coordinates of the vertices obtained by the second reflection? $b)$ What is the value of $a$ if the sum of the first coordinates of the vertices obtained by the second reflection is 36?