'R × S' means 'R' is the father of S.
'R + S' means 'R' is the daughter of 'S'.
'R ÷ S' means 'R' is the son of 'S'.
'R - S' means 'R' is the sister of 'S'.
Which of the following shows that P is the son-in-law of S?
1
P + Q - R × T ÷ S
2
P ÷ Q + R - T × S
3
P × Q + R - T ÷ S
4
P × Q + R + T ÷ S