(Solved): help  The diagram shows a triangular prism. \( A B C D \) is a horizontal rectangle with \( D A ...

The diagram shows a triangular prism. \( A B C D \) is a horizontal rectangle with \( D A=10 \mathrm{~cm} \) and \( A B=5 \mathrm{~cm} \). \( B C Q P \) is a vertical rectangle and \( B P=6 \mathrm{~cm} \). Calculate a the length of \( D P \), b the angle between \( D P \) and the horizontal rectangle \( A B C D \).