Why do my arrowheads on dimensions disappear on my dimensions at times? I can ussually fix it by selecting a dimension then going to its properties and changing the type of arrowhead. Also if I switch to another layer at times I will only see the arrowheads and not the dimensions. It almost seems like the arrowheads and the rest of the dimension would be on a diffent layer, but if I check the properties they are on the same layer.