A network administrator wants to have the same network mask for all networks at a particular small site. The site has the following networks and number of devices: IP phones – 22 addresses PCs – 20 addresses needed Printers – 2 addresses needed Scanners – 2 addresses needed The network administrator has deemed that 192.168.10.0/24 is to be the network used at this site. Which single subnet mask would make the most efficient use of the available addresses to use for the four subnetworks?