Ok, so first we need the equation. So we know that v=b*w*h. We know that the base is 4 inches and the width is 4 inches as well. So we get the equation v=4*4*h. The volume is also given so the equation changes to 56=4*4*h. So first we multiply the numbers we have to get 56=16*h. Then we divide 16 on both sides. 56/16 is 3.5. We end up with 3.5=h. So the answer is 3.5 inches. You can also put this back in to make sure it is right. To 56=4*4*3.5 is true. So therefore, the answer is 3.5 inches.