A $4,636kg$ rocket is set for vertical firing. If the exhaust speed is $1\mathrm{.}816\frac{m}{s},$ at what rate $($in kilograms$/$second$)$ must the gas be ejected to supply the thrust needed to give the rocket an initial upward acceleration of $27\mathrm{.}2\frac{m}{s^2}?$

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