Workbench 11 rookie,; how and when to use displacement supports

[gkd11]

i'm a Workbench 11 rookie;anyone knows how, why and when to use elastic, remote/displacement supports. Also is standard earth gravity to be used in all structural Analysis on the groud?

 

[gamebull]

1.remote one is used in farther force.displacement is nearly one.
2.yes.all structural analysises has a default gravity.