Can Yahoo mail advise when sent mail has been opened like it does when my Yahoo questions have been answered?

For time sensitive material, it would be useful to know that the sent mail has arrived and been opened by the recipient on time as with faxes. How does Yahoo mail do this and what do I have to do to set it up?Can Yahoo mail advise when sent mail has been opened like it does when my Yahoo questions have been answered?
It doesn't work with Yahoo Mail Classic or New Yahoo Mail. Mail plus has the read receipt option, but it is not a free service.





Note: even when using mail plus or any of the other mail progs, you do not have the guaranty that you get a read receipt because a recipient can opt out of sending such notices. Reason behind this: by denying a read receipt, you make sure that spammers don't know whether they hit a real mail address.