Answer:
Clouds of gas and dust as well as new star formation are typically seen in Spiral galaxy
Explanation:
The ingredients for star formation are gas and dust, a spiral galaxy is a group of stars that are together as a consequence of the gravitational pull between them and, as the name said it, has a spiral shape.
They are composed for a central bulge, a disk (in which a spiral arms structure can be seen), gas and dust. Because of the presence of gas and dust, star formation is possible.
Answer:
Explanation:
Given
mass of lumber jack 
mass of floating log 
velocity of lumber jack =3.74 m/s (w.r.t. shore)
conserving momentum
Initial momentum=Final momentum



(b)For second Log
Conserving Momentum
Initial momentum of log and Lumber jack=Final momentum of log and lumberjack

u is final velocity of lumberjack and log


To be honest, there's no sure way to answer that, because you haven't defined your terms and we can't be sure of what j or s might be.
Tell you what I'll do:. I'll assume definitions for j and s, and then I'll answer the question that I invented.
Assume that j stands for Joule, the unit of energy. And assume that s stands for 'second', the unit of time.
Then j/s is the rate of transferring energy or doing work.
Its unit is the Watt, equivalent to 1 Joule per second.
In your system of notation, it would be 'w' .
I believe it would be weight. mass never changes.