For any given substance, the heat capacity of a body is directly proportional to the amount of substance it contains (measured in terms of mass or moles or volume). Doubling the amount of substance in a body doubles its heat capacity, etc.
Conventional soft contacts can last up to a year; conventional rigid gas permeable (RGP) contact lenses can last even longer. Frequent or planned replacement contact lenses last one to several months. Disposable contacts last from one day (daily wear) to up to two weeks (extended wear).
Your prescription can be found on the box on your contact lenses. This is law that your lens prescription must be there and you use it to place your order online. Your prescription is valid for a minimum of 1 year from the date your eye care doctor gives you the prescription. In some states it's 2 years.