Expected Levels. Total hardness in freshwater is usually in the range of 15 to 375 mg/L as CaCO3. Calcium. hardness in freshwater is in the range of 10 to 250 mg/L, often double that of magnesium. hardness (5 to 125 mg/L). Typical seawater has calcium hardness of 1000 mg/L, magnesium.
Part of the Storage management glossary: A physical address is a binarynumber in the form of logical high and low states on an address busthat corresponds to a particular cell of primary storage(also called main memory), or to a particular register in a memory-mapped I/O(input/output) device.
(The physical machine address is also known as a Media Access Control or MAC address .) A table, usually called the ARP cache, is used to maintain a correlation between each MAC address and its corresponding IP address.hen an incoming packet destined for a host machine on a particular local area network arrives at a gateway, the gateway asks the ARP program to find a physical host or MAC address that matches the IP address.