What is the sub network number, of the host with this IP address of 172.16.66.0/21?

When the pc version of the spreadsheet program became available, the ibm pc quickly became the top-selling personal computer?

Technician a says that a dry sump system uses no oil storage sump under the engine. technician b says that a wet sump system uses no oil storage sump under the engine. who is correct?

For a typical middle-income family, what is the estimated cost of raising a child to the age of 18? $145,500 $245,340 $304,340 $455,500