Hello sir/madame; I'm faculty graduated chemical engineer. I can take on your job accurately and completely ONLY IF you will provide the reference from which I'll solve the 8 problems. I would prefer to receive my payment via freelancer milestone to build my reputation, it is my only demand and I am agree with you to receive it after work completion. I have accounts like Skype, Viber, Whats App, yahoo mail, Gmail, ... which provided upon request to facilitate our business communication. Contact me we can negotiate about anything you want. Good luck Best esteem Eng Noha0Nabil