This link takes you to a discussion of the experiment Boyle performed, the data he gathered and his picture. His law gives the relationship between pressure and volume if temperature and amount are held constant. If the volume of a container is increased, the pressure decreases. If the volume of a container is decreased, the pressure increases.
You will be paid an annual salary of Â£40,000 gross. . You will receive a car allowance of Â£350 per calendar month for you to use your private car and you will be reimbursed the mileage you do on company business at 40p per mile for the first 10,000 miles per tax year and thereafter at 25p per mile. am presuming car allowance will be fully taxed as salary and mileage paid Gross. Note it is very unclear from your post if this assuption is correct. At face value it looks like your boss is using the most tax efficient system for paying you for the car.
Gross salary is what is agreed between you and your employer. Net salary is what you get after statutory and other deductions. To cite an example: Gross salary consists of: Basic Pay, Dearness Allowance, House rent Allowance, Conveyance Allowance, etc.et Salary is gross salary less the deductions which are made on account of statutory compliances(like PF, ESI, Income Tax, Professional Tax) and other dues (Like Loans and Advances taken) which you owe to the Company and Legal dues if any.