Online teaching may be mandatory in certain situations, such as during a public health crisis when in-person instruction is not possible. However, in general, the decision to teach online is typically made by educational institutions or individual educators based on their specific circumstances and needs. Some institutions may require a certain percentage of courses to be offered online, while others may leave it up to the discretion of the instructor. Ultimately, the requirement for online teaching depends on the policies and guidelines of the specific educational institution. **

RCD (Residual Current Device) is not mandatory for personal protection in all situations, but it is highly recommended for electrical safety. RCDs are designed to quickly disconnect power in the event of a fault, reducing the risk of electric shock. While not always required by law, using RCDs in homes, workplaces, and other settings can greatly enhance safety and prevent accidents. It is important to follow local regulations and guidelines to determine when and where RCDs are necessary for personal protection. **

No, Nintendo Switch Online is not absolutely mandatory to enjoy playing games on the Nintendo Switch. While subscribing to Nintendo Switch Online provides access to online multiplayer features, cloud saves, and a selection of classic NES and SNES games, many games can still be played offline without a subscription. However, some games do require a Nintendo Switch Online subscription to access their online multiplayer modes. Ultimately, the decision to subscribe to Nintendo Switch Online depends on how important online multiplayer and the other features are to the individual player. **

A camera is not mandatory for online classes, but it can be helpful for certain activities such as virtual meetings, presentations, or group discussions where video communication is important. Some instructors may require students to have a camera for participation or engagement purposes, but in general, it is not a strict requirement. Students can still actively participate in online classes using just audio or text communication if they do not have a camera. **

A camera is not mandatory during online classes, but it can be helpful for engagement and participation. Some instructors may request that students have their cameras on to create a more interactive and engaging learning environment. However, there may be valid reasons for students to not have their cameras on, such as privacy concerns or technical limitations. Ultimately, it depends on the specific requirements and expectations set by the instructor or educational institution. **

It is not mandatory to select an airplane seat online. Many airlines offer the option to select a seat during the online check-in process, but it is not required. Passengers can also choose their seat at the airport check-in counter or have a seat assigned to them at the gate. However, selecting a seat online can provide more options and ensure that passengers get their preferred seat. **

USK is not mandatory in Germany, but it is highly recommended for video games to be rated by the USK before being released in the country. The USK rating helps inform consumers about the content of the game and ensures that it is appropriate for certain age groups. While it is not legally required to have a USK rating, many retailers and platforms may choose not to sell or distribute games that have not been rated by the USK. **

In the United States, recess is not mandated at the federal level, but many states and school districts have policies in place that require a certain amount of recess time for students. However, the specifics of these policies can vary widely. Some schools may have mandatory recess periods, while others may leave it up to individual teachers or schools to decide how to incorporate breaks into the school day. Ultimately, the decision on whether recess is mandatory depends on the specific policies of the school or district. **