Answer:
4046.56 cm3
Step-by-step explanation:
The base is made by 5 isosceles triangles, with one side of 14 cm, and the opposite angle of [tex] \frac{360} 5 = 72° [/tex]. Each of the other angle is [tex]\frac{180-72} {2} =54°[/tex]. From there, you can calculate the height of each base triangle as in [tex]\frac {h} 7 = tan54[/tex] or 9.634...cm.
Your volume will be [tex]5 * \frac {(14 * 9.634)} 2 * 12 = 4046.56 cm^3[/tex]