A cell that carries out the final response or function of a particular process. The main effector cells of the immune system, for example, are activated lymphocytes and phagocytesâthe cells involved in destroying pathogens and removing them from the body.
Best Answer: Yes you can track it online here: https://tools.usps.com/go/TrackConfirmAc... The tracking number should look like this: CP 000 000 000 US. You can find it on the receipt, and the customs form you filled out.
USPS Tracking. The most common tracking number format is 20 digits (e.g. 9999 9999 9999 9999 9999), or a combination of 13 alphabetic and numeric characters, usually starting with 2 alphabets, following by 9 digits, and ending by US (e.g. EA 999 999 999 US).