Hello,i am interested.
Before replying to a post, always check the date when it was last active.
So, for example, you respond to someone who left this offer more than 2.5 years ago plus he has also not been active for 2.5 years. The chances that you will be hired for this job are less than one in a billion. 
Simply say that his chances of getting hired for this job is zero (0)

, op posted this and never did reply here again, and like you said, this was about 3 year ago, even if op was or is still active, there chances this offer will still be available is also zero (0).
And besides, for offers like this, it's best for the interested party to take payment upfront before carrying out the task, as there is no guarantee that the op will pay the participant(s) at the end of the day after he or she, or they(if they are multiple persons) must have spent their time spamming other people's tweets for op and what ever business or service he or she is into.