The formula for calculating the area of a triangle is :-
Area of a △ = (Base * Height)/2
Now, according to question,
Base = 10.2 in
Height = 8 in
Now, substitute these values in the formula.
Area = (10.2 * 8)/2
= (81.6)/2
= 40.8 in²
=> So the area of the given △ is 40.8 in² ( Option C ).