A cone is formed by rolling up a 90 degree sector of a circle having a radius of 8 inches. Find the volume of the cone to the nearest tenth

l is equal to 8. I am having a problem finding the radius and the height. I want to say the lateral area and the base form a 60 degree angle, I am not told this so do not want to assume anything. Help to figure out how to start of where to start would be great thanks.