A beam is subjected to a force system shown in figure. This force system can be reduced to:
1
A single force of 50 N (downward) at 2.5 m from D
2
A single force of 50 N (downward) at 2.5 m from A
3
A single force of 50 N (upward) at 2.5 m from A
4
A single force of 50 N (upward) at 2.5 m from D