Duplex printing allows printing on both sides of a paper, which can significantly reduce paper consumption and costs associated with buying paper. This makes duplex printing the best feature for cutting costs on consumables.
References:
* CompTIA A+ Core 1 Exam Objectives Section 3.6: Given a scenario, deploy and configure multifunction devices/printers and settings.

The most likely reason for a computer showing an APIPA address after being plugged into a network port is that the PC is unable to contact a DHCP server1. Automatic Private IP Addressing (APIPA) is a DHCP fail-safe that protects a computer system from failure. It invokes a standby mechanism for local Internet Protocol version 4 (IPv4) networks supported by Microsoft Windows. With APIPA, DHCP clients can obtain IP addresses even when DHCP servers are not functional1. The other options are less likely to be the cause of the issue1.

The projector is overheating and needs to be cleaned. A common cause of projector shutdown is overheating, which can be triggered by dust accumulation, blocked vents, or faulty fans. The projector has a thermal protection circuit that turns it off when the temperature reaches a certain level, and it will not turn back on until it cools down. To prevent this issue, the projector needs to be cleaned regularly and placed in a well- ventilated area. The video cable, the bulb, and the outlet are not likely to cause the projector to turn off intermittently.
Reference: [CompTIA A+ Core 1 (220-1101) Certification Study Guide], page 18.

The correct answers are D. The overall IT cost goes down and F. Upgrading applications is easier.
Application virtualization is a technology that allows users to run applications without installing them on their devices. The applications are stored and executed on a remote server, and the users can access them through a network connection. Application virtualization has several benefits, such as12:
*The overall IT cost goes down: Application virtualization reduces the need for hardware, software, and maintenance costs, as the applications are centralized and managed on the server side. This also saves energy and space, as fewer physical machines are required to run the applications. Additionally, application virtualization can reduce licensing costs, as the applications can be delivered on-demand and based on usage.
*Upgrading applications is easier: Application virtualization simplifies the process of updating and patching applications, as the changes can be made on the server side and pushed to the users instantly. This eliminates the need for manual installation and configuration on each device, and ensures that all users have the latest version of the applications.
Other benefits of application virtualization include123:
*Allows the running of legacy apps: Application virtualization can enable users to run applications that are developed for older or incompatible operating systems, such as Windows 7 or XP. This can extend the lifespan of legacy applications and avoid compatibility issues.
*Enables cross-platform operations: Application virtualization can allow users to run applications that are designed for different platforms, such as Windows apps on iOS, Android, macOS, or Chrome OS. This can increase the accessibility and mobility of the applications and enhance the user experience.
*Improves security and compliance: Application virtualization can isolate the applications from the underlying operating system and hardware, preventing malware or unauthorized access from affecting them.
This can also protect the data and settings of the applications from being tampered with or lost. Furthermore, application virtualization can help enforce compliance policies and regulations, as the applications can be controlled and monitored by the server.
References:
1: 5 Benefits of Virtualization - IBM Blog
2: Benefits of Application Virtualization - AppsAnywhere
3: What is Application Virtualization? | VMware Glossary

When print jobs remain stuck in the printer queue despite successful network communication (indicated by successful ping replies) and no issues with paper supply or toner levels, a common reason can be that the first job in the queue requires manual intervention, such as paper to be fed into a manual feed tray. Printers often pause the entire print queue if the first job requires a specific type of paper or manual insertion that hasn't been addressed, preventing subsequent jobs from processing.
References:
* CompTIA A+ Core 1 (220-1101) Exam Objectives, specifically the sections on troubleshooting printers, which include understanding various reasons why print jobs might get stuck in the print queue.
* Knowledge of printer operation and common print job issues, with an emphasis on how printers handle manual feed tray requirements and the impact on the print queue.