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You should use the View > Page Source feature of your browser, identify the id or class of the elements which generate those items, then add something like this to your theme’s style.css file:
#some-id {display: none;} (for elements identified by id)
.some-class {display: none;} (for elements identified by class)
Copy the style.css file first, so you can restore if all goes horribly wrong!
PS Most of those things are so-called ‘meta’ elements; that might be a good thing to start looking for.