Answer of q.8
Refer the following link for the answer similar to your query :
https://www.meritnation.com/ask-answer/question/at-a-height-of-1500-root-3-m-find-the-speed-of-the-jet/some-applications-of-trigonometry/1404437
https://www.meritnation.com/ask-answer/question/at-a-height-of-1500-root-3-m-find-the-speed-of-the-jet/some-applications-of-trigonometry/1404437