Answer:
B = 125 square mm, P = 51 mm, I = 15mm
Step-by-step explanation:
This looks like a equilateral pyramid.
So all the faces are equilaterals with side lengths 17 mm. ...
So B = base area = 125 square mm
P = perimeter = 17 + 17 + 17 = 51 mm
I = slant height = 15 mm.
verify B = (1/2)* 17 * ( 17/2)*root(3) = 125.14 square mm