Can HTML source tell me what action should be taken to 'submit'/'go'/'login'?

In a successful sub, I have passed four ranges to a webform and retrieved the result. The 'submit' (clicking the submit button) action was accomplished via

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Now in another webquery, I cannot seem to achieve the same results. Is there something in the HTML that will tell me which action is required within my code to be successful. The HTML of the button I need to activate follows:

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which unlike my previous webquery, does not contain the <input>, <name>, or <type> attributes.

ForumHTML.txt

Thanks,