Answer:
Below!
Step-by-step explanation:
First you can find the area of the triangular shape using A = bh /2
A = (12)(5.8) / 2
= 34.8 km^2
Now you can just multiply this area by the length of the prism
V = Area x height
= (34.8)(10)
= 348 km^3
Hope this helps! Best of luck <3