REALLY!!! Need help please!!! Been struggling on this!!! I will give you brainliest if you answer it!!!!

Answer:
199.5in^3
Step-by-step explanation:
To do this we first need to find the area of the triangle to do that we can do 3.5*2=7
(since there are two triangles we can do it like this to make it easy)
then we can multiply it like so
7*28.5=199.5
Hope this helps :)