Answer:
300cm
Step-by-step explanation:
First you get the length, width, and height. The length is 15, the width is 12, and the height is 10.
15*12=180
Since their is 2 you multiply by 2
180*2=360
12*10=120
Since their is 2 you multiply by 2
120*2=240
Then you divide by 2 since it is a triangle but before that you add the products up
360+240=600
600/2=300