If the following images were acquired such that significant areal color variation indicates different phases (i. e. these micrographs feature phase-contrast), how many distinct phases are present in each micrograph? These are grayscale images, so color variation ranges from white -> gray -> black. These are space-filing structures. (All area within the images is part of the material specimen being imaged). I am intentionally not telling you what these materials are, so you can practice seeing and identifying phases within generic microstructures.