The correct answers are A. Identify the location of devices that utilize 2.4GHz and D. Map all of the wireless signals in the restaurant. In order to troubleshoot the issue, the technician should first identify the location of devices that utilize the 2.4GHz frequency, as this can cause interference with the wireless signal. Additionally, the technician should map all of the wireless signals in the restaurant in order to identify any potential sources of interference. Checking to see if the phones are IJTP or STP lines, testing to see if the copper electrical wires are causing interference, verifying T568B is being used in the wiring closet patch panel, and scheduling timed router reboots throughout the day are not necessary steps for troubleshooting this issue.

PaaS (Platform as a Service) is a cloud computing model in which a provider offers a platform that allows developers to create, run, and manage applications without the complexity of building and maintaining the infrastructure. An application development environment is a valid use for PaaS. Reference: CompTIA A+ Certification Exam Objectives 1001, 1.7

If the touch-screen features on a Windows device have stopped working, a technician should check the Tablet/PC settings. The Tablet/PC settings contain options for configuring the touch-screen features on a Windows device. By checking the Tablet/PC settings, the technician can ensure that the touch-screen features are enabled and configured correctly.
If the touch-screen features on a Windows device have stopped working, a technician should check the Tablet/PC settings. The touch-screen settings may have been disabled or there may be a driver issue that needs to be resolved. Reference: CompTIA A+ Certification Exam Guide, pg. 536

According to Dell Community, the Wi-Fi antenna is located in the top of the LCD display housing. It consists of two elements, fed by two cables, a white main designated on the Wi-Fi card by a white triangle, and a black auxiliary designated on the Wi-Fi card by a black triangle1.

To increase the volume on a laptop using only a keyboard, a user can press and hold down the Fn key while pressing one of the function keys (usually F1-F12) that has an icon representing volume up.