The Associative Laws say that it doesn't matter how we group the numbers (i.e. which we calculate first) ... ... when we add : (a + b) + c = a + (b + c). ... or when we multiply : (a Ã b) Ã c = a Ã (b Ã c).
To complete the PCT in two months (or less) you will need to average approximately 43.6 mi / 70.2 km per day (this was my longest day on trail).
PCR is often used for testing donated blood. However, it cannot be used for HIV tests, because a formula is yet to be worked out to specifically detect the existence of HIV virus. A window period lasts for 22 to 30 days on an average. However, for some individuals, it could even be more than three to six months. A lot depends on the body type of the individual. Antigen Testing and Nucleic Acid Testing (NAT) can curtail the window period to 16 days and 12 days respectively.