Identify the statement(s) which is/are true. (a) ` f( x , y )= e^( y/ x )+tan y/ x` is a homogeneous of degree zero. (b)` xln y/ x dx+ y^(2)/ x *sin^-1(y/ x ) dy=0` is a homogeneous differential equation. (c)`f( x ,y )= x^(2)+sinx cosy` is a non homogeneous. (d)`( x^(2)+ y^(2))dx-(x y^(2)-y^(3))dy=0` is a homogeneous differential equation.