a$)$ An intervalometer will be used to control intervals between exposures for a flight campaign, the ground speed will be maintained at $260k\frac{m}{h}$ while the average scale will be $1$:$15000.$ The photo format will be $240mm$ and the camera focal length will be $160mm.$ The vertical exaggeration will be $4\mathrm{.}5.$ The model distance to eye base ratio is $7\mathrm{.}5.$ Calculate the exposure interval.

$(5$ marks$)$