A thin plate moves between two parallel horizontal stationary flat plates at a constant

velocity of $5\frac{m}{s}.$ The two stationary flat plates are $4$ mm apart, and the medium between

them is filled with oil whose viscosity is $0\mathrm{.}9$ Pa $-$s$.$ The part of the plate immersed in oil at

any given time is $2-m$ long, and $0\mathrm{.}5$ m wide. If the thin plate is placed equidistant from

both plates above and below it$,$ calculate the drag force required to maintain its motion.