
Patrick B. answered 04/22/21
Math and computer tutor/teacher
(4)
if Q then T-->E and G -->T since P is given.
So if Q then G-->T--->E
if Q then G-->E
Therefore, Q or not(G-->E)
(5) If ~W then ~W --> (X -->W)
Which forces X-->W
By contrapositive, ~X must hold..
Therefore, ~W --> ~X
(6) if ~L then J must hold.
then K-->L
then ~K
(7) since ~D, then by 1, S must hold
By 2, ~D --> K, so K since ~D
(8) Since ~H, ~F-->M;
since A, E-->~F
therefore, E-->~F-->M
(9) Since ~G, G or ~A follows by (1)
Since ~G, ~A must hold;
then by 2 , C-->A
But ~A, so ~C by contrapositive
(10) Since N, J-->P must hold;
By 2, N-->J;
But N holds, so must J.
Therefore P
(17) Since ~R, then ~H and Q-->R
By contrapositive, ~Q holds;
Therefore, by 1, F
(18)
Since ~D, ~C-->A by 2 and
~A by 3...
Therefore by contrapositive, C must hold
therefore, By contrapositive of 1, ~B