Answer:
increase
Explanation:
At the skate park when a skateboarder wants to skate down a ramp, the skate boarder wishes to move faster and with speed so that it help him to skate more time. This can only be achieved if the all the forces acting on him will increase as he skates down the ramp without much of the frictional force acting on the wheels of the skate board. The less friction force acts on the wheel, the more he can skate with more speed.
Thus, the skateboarder wants the force to be increase that is acting on him.
Answer : At constant pressure work is done by the system on the surroundings.
Explanation :
Work done : Any quantity that flows across the boundary of a system during a change in its state and it completely convertible into the lifting of a weight in the surroundings.
Formula for work done is:

Sign convention :
- When volume expand then system work that means work done by the system.
w = (-ve)
- When volume compress then surrounding work that means work done on the system.
w = (+ve)
The given reaction is:

This is a evaporation process in which phase changes from liquid state to gaseous state at constant temperature.
At constant pressure, work depends only on volume.
In evaporation process, the volume expand that means work is done by the system on the surroundings.
Sign convention is, w = (-ve)
Thus, at constant pressure work is done by the system on the surroundings.
The reaction is actually endothermic because delta H is positive, indicating that it absorbing heat.
For water to freeze it would need to be 32 degrees Fahrenheit or 0 degrees Celsius.