Enlarge or reduce the image size in a browser when images are bigger than the browser window
Internet Explorer and Mozilla Firefox: How to use the Zoom-in Zoom-out Feature
http://www.itg.ias.edu/content/internet-explorer-and-mozilla-firefox-how-use-zoom-feature
select custom zoom sizes Internet Explorer: make visible the status bar, click on zoom feature icon located right side of status bar; choose fixed or custom zoom selections.

Select custom image resizes Firefox: right click on image; select view image; image will resize as you change the size of browser window; click on icon to toggle between full size and variable size.

Chrome Browser: How to use the Zoom-in Zoom-out Feature
https://support.google.com/chrome/answer/96810?hl=en

Select custom zoom sizes other browsers use browser help system.

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