Be careful since biology dissertation is more specialised than any management project

It would be more helpful if you write you have been freelancing for students.

You can be scammed in proof reading as well. Just choose carefully.

Next time either don't work without advance payment or make them clear if you don't receive your payment within an hour you will post the entire work

50 pages per day are too much. Decline some of the work then otherwise it is bound to get substandard

If the company is giving the complete payment to the writers then how is it sustaining the site. It requires money to run a site and nobody is here for charity.

For large organisations, social responsibilities are also part of their work culture but for small businesses only profit is the bottom line.

the quality of your writing will decide the pay you get.

You wil have to rephrase your entire work. You can use the information but would have re-write the composition

How can you be sure if the website is from uk or us or some other country

If a person is a lecturer and giving out assignments and acting as freelance writer, isn't it incorrect ?

You shouldn't be promoting any website. That's against rules