Disable submit button

Hello
Are there any javascript events related to your plugin ?
I want to keep disabled the form submit button if the checkbox is not checked or if it expires.
In some html pages, in which I have added the captcha manually, I do that with javascript events that captcha has, such as:
+//Captcha
+var googleCaptchaSuccess = function () {
+ jQuery(‘.red-button.contact-us-button’).removeAttr(‘disabled’);
+ };
+
+var googleCaptchaExpired = function () {
+ jQuery(‘.red-button.contact-us-button’).attr(‘disabled’,’disabled’);
+ };
+
+var googleCaptchaError = function () {
+ jQuery(‘.red-button.contact-us-button’).attr(‘disabled’,’disabled’);
+ };
+
+jQuery(document).ready(function(){
+ jQuery(‘.red-button.contact-us-button’).attr(‘disabled’,’disabled’);
+ });

Does this plugin has something similar ?
Thanks.

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