Answer :
we are given
speed is 850mi/h
we know that
1 mile =1609.34 metre
1 hour = 3600 second
now, we can replace 1mi and 1hour
[tex] 850mi/h=850*\frac{1609.34}{3600} m/s [/tex]
now, we can solve it
379.98306
[tex] 850mi/h=379.98306 m/s [/tex]...........Answer