So you not only know<span> how fast it is going, but where it is going.</span>
Answer:
The mass of the 500 series bullet train is 181.4 tonnes.
Explanation:
The momentum is given by:

Where:
m: is the mass =?
v: is the velocity = 261.8 km/h
p: is the momentum = 13194098.64 kg*m/s
By solving the above equation for "m" we have:

Therefore, the mass of the 500 series bullet train is 181.4 tonnes.
I hope it helps you!
Answer:
The mass of the cargo is 
Explanation:
From the question we are told that
The radius of the spherical balloon is 
The mass of the balloon is
The volume of the spherical balloon is mathematically represented as

substituting values


The total mass the balloon can lift is mathematically represented as

where
is the density of helium with a value of

and
is the density of air with a value of

substituting values


Now the mass of the cargo is mathematically evaluated as


Nitrogen, oxygen, and argon
P1v1/t1 = p2v2/t2
p1=p2, v1=.2, t1=333, t2=533
we can find v2 from this
be aware, temperature must be in Kelvin.