Multi-select: Knowing that "adding salt to a liquid decreases the melting point of that liquid", how would one answer "If a person is running a salad bar and needs to keep the bar cold, and therefore the ice frozen, they might"

OPT:
1). pour sodium over the ice.
2). put the ice in the sun.
3). melt the ice on a stove.
4). throw the ice away....A:
1).