The coordinates of S would be (4, 4)
In order to find this, we need to know that the value of midpoint (M) points will always be the average of S and T's points. This is because it is the midpoint. Therefore we can use the following formula.
Value of x
(S + T)/2 = M
(S + 0)/2 = 2
S + 0 = 4
S = 4
Then we can do the same for the y values
Value of y
(S + T)/2 = M
(S + 6)/2 = 5
S + 6 = 10
S = 4