<u>Answer:</u> The elevation in boiling point is 1.024°C.
<u>Explanation:</u>
To calculate the elevation in boiling point, we use the equation:

where,
i = Van't Hoff factor = 2 (for NaCl)
= change in boiling point = ?
= boiling point constant = 
m = molality = 1.0 m
Putting values in above equation, we get:

Hence, the elevation in boiling point is 1.024°C.
Your weight would change but not your mass, the moon has less gravity so therefore you are going to be lighter :-)
Before you start working on any motion problem, YOU decide which direction you're going to call 'positive'. Everybody almost always calls UP positive, and the acceleration of gravity points down, so it winds up negative. But you could just as well call DOWN the positive direction. Then, the cannonball is fired with a negative vertical speed, and the acceleration of gravity eventually robs all of its negative speed, and makes it start falling in the positive direction. The whole thing is your choice.
Work= (force)(distance)
178= m(9.81)x0.5
178=m(4.905)
178/4.905=m
His mass is 36.3 kg