Answer: Because the janitor is aware of your plight, the first thing to consider is this being a trick to extort you or to waste your time. After considering it to be a trick, you still have to consider it to be true. This makes it a game of 50:50 chance ( that is equal chance to loss or win).
To approach this situation, you have to define an agreement with the janitor. The agreement should be "send me the chemistry master and I will pay you after I have written the exam to confirm it is actually a chemistry master or pay you 1/10 of your amount if it is not, to compensate your efforts". After sending this agreement, you should focused on your studies like you're not expecting a positive response from him.
Negotiation should not be involved in the agreement, as it will waste your time of studies.
<span>Appling science in daily life has become the norm of today's world by deriving and presenting a easier outlook on things. Thus technology is the practical application of science that is helping to solve the problems. But this use of technology has become so rapid and too inclusive that it is reducing the human point of view.</span>