I'm not really sure what specific answer they're looking for, but if it's an open-ended question, then let's think about it this way...
A light year, is the distance it takes for light to travel in a year. If an object is 50,000 light years away, then by the time the light travels to us, 50,000 years has passed. We are looking at a 50,000 year old image of that object. (ignoring gravity and spatial expansion fun stuffs)
First, we assume this as an ideal gas so we use the equation PV=nRT. Then, we use the conditions at STP that would be 1 atm and 273.15 K. We calculate as follows:
PV= nRT
PV= mRT/MM
1 atm (.245 L) =1.30(0.08206)(273.15) / MM
MM = 118.94 g/mol <--- ANSWER
The net force is the total force. Add 4 and 2 together and you get 6. Since 5 N are pushing against it, you subtract that from 6. The net force is 1 N.
Answer: Migration and hibernation
Explanation: look it up ;)
The coefficient of static friction between the puck and the surface.
In fact, that coefficient describes exactly how "hard" it is to cause the puck to start moving, if it starts from an idle condition.
