Remember that
The area of a triangle is equal to
A=(1/2)(b)(h)
In this problem
b=36 km
h=XU
step 1
Find the length segment XU
In the right triangle XWU
we have
sin(67)=XU/WU -----> by opposite side divided by the hypotenuse
XU=WU*sin(67)
XU=44*sin(67)
XU=40.50 KM
step 2
Find the area
A=(1/2)(36)(40.50)
A=729 Km2
option B