A machine gun fires bullets, each with mass m = 55 \text{ g}m=55 g at a speed of u = 450 \text{ m.s}^{-1}u=450 m.s
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. The gun fires 5.05.0 bullets per second. Let's use it as a rocket engine. What thrust does it produce?
You have just copied these exactly from the online course book. Unless you can take the trouble to write them in a more readable form I'm not going to struggle to work out what your curly brackets and 'text' means.
Also, list the equations/principles you think might be relevant and I'll comment
A machine gun fires bullets, each with mass m = 55 g at a speed of u = 450 m/s.
The gun fires 5.0 bullets per second. Let's use it as a rocket engine. What thrust does it produce?
Thrust _____ N.
Now that's much easier to read. It's always worth checking that the format looks right