Information and communication technology is referred to as useful energy because it enables the efficient transmission and processing of information, leading to increased productivity and effectiveness in various tasks. Just like energy is essential for powering machines and devices, ICT provides the necessary tools and resources for communication, data storage, and problem-solving. It plays a crucial role in powering modern economies and societies by facilitating connectivity, innovation, and collaboration. **

Yes, energy-saving measures are useful because they help reduce energy consumption, lower utility bills, and decrease the environmental impact of energy production. Simple measures such as using energy-efficient appliances, insulating homes, and using LED light bulbs can make a significant difference in reducing energy usage. Additionally, energy-saving measures can contribute to a more sustainable and environmentally friendly way of living. **

A mini fridge can be useful in certain situations, such as in a dorm room or small apartment where space is limited. However, mini fridges are generally less energy efficient than full-sized refrigerators, so they can be considered energy hogs in comparison. It's important to consider your specific needs and energy usage when deciding whether a mini fridge is the right choice for you. **

Homework portals can be useful because they provide a centralized platform for students to access assignments, resources, and important information from their teachers. This can help students stay organized and on track with their work. However, they can also be not useful if they are not user-friendly or if teachers do not update them regularly, leading to confusion and frustration for students. Overall, homework portals can be a valuable tool for enhancing communication and efficiency in the learning process when used effectively. **

Both Ancestry and MyHeritage are useful for genealogy research, but they have different strengths. Ancestry has a larger database of historical records and documents, making it a valuable resource for building family trees and finding historical records. On the other hand, MyHeritage offers a more global approach with a focus on international records and DNA testing, making it useful for those with ancestors from outside the United States. Ultimately, the choice between the two depends on the specific needs and research goals of the individual genealogist. **

Mosquitoes play a role in the ecosystem as a food source for other animals such as birds, bats, and fish. However, their primary role as disease vectors outweighs their usefulness. Mosquitoes are responsible for transmitting diseases such as malaria, dengue fever, Zika virus, and West Nile virus, causing significant harm to human populations worldwide. Efforts to control mosquito populations are important for public health and reducing the spread of these diseases. **

Yes, blackbirds are useful in various ways. They help control insect populations by feeding on pests like caterpillars, beetles, and grasshoppers. Additionally, they play a role in seed dispersal by consuming fruits and spreading seeds to new locations. Blackbirds also contribute to the ecosystem by serving as prey for larger predators, helping to maintain a balanced food chain. **

Aikido can be useful for self-defense in certain situations, as it focuses on redirecting an attacker's energy rather than meeting force with force. It also promotes physical fitness, flexibility, and mental discipline. However, its effectiveness may vary depending on the practitioner's skill level and the specific circumstances of an altercation. Ultimately, whether Aikido is useful or not depends on the individual's goals and how well they are able to apply the techniques in real-life situations. **