A Firebox backup image typically includes several critical components necessary for restoring and maintaining the device's functionality. These include the Fireware OS, which is the operating system the Firebox runs; the configuration file, which contains the device's settings and customizations; the feature keys, which enable various licensed functionalities and services; and certificates, which are essential for establishing secure connections and authenticating the device. Therefore, the most appropriate items included in a Firebox backup image are Fireware OS, configuration file, feature keys, and certificates.
The number of clients able to connect to the internet at the same time is limited to 50 because the DHCP address pool on the trusted interface has only 50 IP addresses. This means that only 50 devices can obtain an IP address dynamically from the Firebox at any given time. If there are only 50 IP addresses available in the DHCP pool, once they are exhausted, no more clients can receive an IP address until a lease is released.
To avoid a network outage for clients on the trusted network when changing the interface IP address from 10.0.40.1/24 to 10.0.50.1/24, you should add 10.0.40.1/24 as a secondary IP address for the interface. This way, the interface will temporarily have both IP addresses, allowing clients on the old 10.0.40.0/24 subnet to still communicate while you transition to the new 10.0.50.0/24 subnet.

Eth2 is a member of the alias Optional-1. Given this, it is part of the Any-optional, Optional-1, and Any aliases. The Any-optional alias includes all optional interfaces, which include Eth2. Optional-1 is explicitly the alias for Eth2. The Any alias includes all interfaces, encompassing Eth2 as well.

In order for client computers on the trusted network (10.0.10.0/24) to communicate with the server at 10.0.20.100 on the optional network, a static route must be configured on the Firebox. The correct route would be directed towards the 10.0.20.0/24 network, with the gateway being 10.0.2.254, which is the router on the optional network responsible for routing traffic to the 10.0.20.0/24 network.