The asymmetrical support arrangement is chosen for a pedestrian bridge because conditions at the right end F do not permit a support tower and anchorages. During a test, the tensions in cables 2, 3, and 4 are all adjusted to the same value T. If the moment at O is to be zero, what should be the value T1 of the tension in cable 1? Determine the corresponding value of the compression force P (enter a positive number) at O resulting from the four tensions applied at A. Neglect the weight of the tower.