Answer:
Height = 19mm.
Step-by-step explanation:
Area of a regular polygon = (A * P) / 2 where A = side / (2 * Tan (π / N)) where, N = Number of sides, A = Apothem, P = Perimeter.
Here A = 5, P = 5*12 = 60 so
Area of the base = (5 * 60) / 2 = 150 mm^2.
Volume = area base * height so
Height = volume / area of base
= 2850 / 150
= 19 mm.