I was working on some questions for homework and for some reason cannot understand how to approach this question

A camera, located 5 km from the launch pad, is tracking the rocket that is fired straight up. When the height of the rocket is 12 km, the camera is rotating at the rate of 1/48 radians per second. What is the speed of the rocket at that instant? Give your answer in km/sec. ?

Any help would be much appreciated thanks!

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