If I increase the amount of baking powder, then the muffins will be taller in height, heavier in weight, and more fluffy/softer in texture because more baking powder causes the muffin to rise more, adding more weight. If I decrease the amount of baking powder then the muffind will be shorter in height, less in weight, and less fluffy/harder because less baking powder will cause the muffins to be shorter in height, lessening the weight.