Mobile images

My site is doing strange things with images, all the images show fine in most views. When on portrait view on mobile some images show way to big. They show fine on mobile landscape. One on the front page and the link images on the posts. The ‘download pdf’ and ‘take test’s buttons.
Any help in resizing these would help. I have tried some CSS fixes that I found in searches but they didn’t work.
Cheers

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