They're too large, but not by much. The real problem is you're way over in total filesize allowed.
Total pix height can be up to 200 pixels tall, but your first two images are slightly over that. Your last one is at 195 pixels.
Filesize allowed is 50,000 bytes. Your pictures are at just about 25,000 bytes each, so you're about 75,000 bytes, which is over the total.
If you have a PC, you can right-click on each image, from the popup menu select 'properties'. In the properties box that displays, you can see a listing for the filesize, and a listing for the image size (dimensions:width and height)
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