I need help on this on my bros

Step-by-step explanation:
By 30°-60°-90° triangle theorem:
[tex]15 = \frac{1}{2} \times c.. (side\:opposite \: to \:30°)\\ c = 15 \times 2 \\ \\ \huge \red{ \boxed{c = 30 \: m}} \\ \\ b = \frac{ \sqrt{3} }{2} \times c.. (side\:opposite \: to \:60°) \\ \\ b = \frac{ \sqrt{3} }{2} \times 30 \\ \\ \huge \purple{ \boxed{b = 15 \sqrt{3} \: m}}[/tex]