Why is the act of getting up “reassuring”?

Please explain the meaning significance of the following quote by answering each of the questions below:

“Now at each instant we are thrust into the world and engaged there. This means that we act before positing our possibilities and that these possibilities which are disclosed as realized or in the process of being realized refer to meanings which necessitate special acts in order to be put into question. The alarm which rings in the morning refers to the possibility of my going to work, which is my possibility. But to apprehend the summons of the alarm as a summons is to get up. Therefore the very act of getting up is reassuring, for it eludes the question, “Is work my possibility?” Consequently it does not put me in a position to apprehend the possibility of quietism, of refusing to work, and finally the possibility of refusing the world and the possibility of death. In short, to the extent that I apprehend the meaning of the ringing, I am already up at its summons; this apprehension guarantees me against the anguished intuition that it is I who confer on the alarm clock its exigency – I and I alone” (Sartre, p. 335).