ok i need help!!!! i give up!!! on my sub box

i have one KOLE AUDIO 15 1,000. i have a box that i making, if u guys could help me out that would help alot. my box is 36" WIDE/ 19" HEIGHT/ 15" DEPTH IM WANTING TO KNOW HOW MANY CUBIC FEET THIS BOX IS. THATS FOR UR REPLYS