Substitute to Find the Value of the Expression $b$ And Height $h$

Multiple Choice

Substitute to find the value of the expression.
-The area of a triangle with base $b$ and height $h$ is given by the formula $A = \frac { 1 } { 2 } b h$ . Find the area of a triangle when the base is $3.4$ centimeters and the height is $5.5$ centimeters.

A) $18.7 \mathrm {~cm} ^ { 2 }$
B) $9.35 \mathrm {~cm} ^ { 2 }$
C) $0.31 \mathrm {~cm} ^ { 2 }$
D) $7.48 \mathrm {~cm} ^ { 2 }$