What is the mass of 5.84 × 10^21 atoms of xenon?

PLEASE ANSWER FAST :)
30 POINTS

Melting and boiling are endothermic processes. this means that these processes absorb energy from their surroundings in order to occur. use this information and the data you collected in the phase change gizmo to describe what happens to the temperature of water when you boil it, then explain why this result occurs.

How much would the freezing point of water decrease if 4 mol of sugar were added to 1 kg of water(k=1.86 c/mol/kg for water and i=1 for sugar

Which change to the system wood cause the freely-moving piston to lower?