In alveolar and blood & blood and tissue gas exchanges - What are the values of $(X_1, Y_1) ; (X_2, Y_2) ; (X_3, Y_3)$ in the picture marked?

Question

( a ) $(X_1, Y_1) = (40, 45) ; (X_2, Y_2) = (104, 40) ; (X_3, Y_3)$ = (95, 40)
( b ) $(X_1, Y_1) = (40, 45) ; (X_2, Y_2) = (108, 40) ; (X_3, Y_3)$ = (90, 45)
( c ) $(X_1, Y_1) = (40, 55) ; (X_2, Y_2) = (104, 40) ; (X_3, Y_3)$ = (95, 45)
( d ) $(X_1, Y_1) = (95, 45) ; (X_2, Y_2) = (104, 40) ; (X_3, Y_3)$ = (45, 40)