What is the value of b for the following triangular prism?

i don't know this at all

B stands for the area of the  triangular base of the prism.

Area of a triangle = hb/2 
h = height of the triangle = 3.75cm
b = base of the triangle = 28mm convert to cm. 2.8 cm

Area of a triangle = (3.75cm * 2.8cm) /2 = 10.5 cm² / 2 = 5.25 cm²

The value of B is 5.25 cm²

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