MCAS Science, Technology/Engineering Practice

Explanation
The full meaning of WWW is World Wide Web.

Explanation
The first generation of computers used vacuum tubes. Vacuum tubes were large glass tubes that controlled the flow of electricity in early computers. They were used as switches and amplifiers for electronic signals. However, vacuum tubes were bulky, consumed a lot of power, and generated a significant amount of heat. These limitations led to the development of smaller and more efficient transistor-based computers in later generations.

Explanation
The Central Processing Unit (CPU) is often referred to as the brain of a computer because it is responsible for executing instructions and performing calculations. It is the main component that carries out the majority of the computer's processing tasks, including fetching, decoding, and executing instructions from memory. The CPU is responsible for coordinating and controlling the activities of all other hardware components, making it the most essential part of a computer system.

Explanation
A mouse is an input device of a computer because it allows the user to interact with the computer by moving the cursor on the screen and clicking on various elements. It is used to select, drag, and drop objects, navigate through menus, and perform other actions. The mouse typically has buttons and a scroll wheel, which provide additional functionality and options for input. Overall, the mouse plays a crucial role in providing input to the computer and enabling the user to control and operate various software applications and functions.

Explanation
A gigabyte is a unit of digital information that is equal to 1,024 megabytes. Therefore, the correct answer is 1024.

Explanation
The function of an acid in a car battery is to act as an electrolyte. An electrolyte is a substance that conducts electricity when dissolved in water or melted. In a car battery, the acid (usually sulfuric acid) dissociates into ions, allowing the flow of electric current between the positive and negative terminals of the battery. This process is essential for the battery to generate and store electrical energy, which is then used to power the car's electrical systems.

Explanation
Ethyne, also known as acetylene, is used in the ripening of fruits. When ethyne gas is released in a closed environment with unripe fruits, it accelerates the ripening process by triggering the production of a plant hormone called ethylene. Ethylene is responsible for various physiological changes in fruits, including softening, color change, and aroma development. This process is commonly used in the agricultural industry to control the ripening of fruits and ensure a consistent supply to the market.

Explanation
Lead is the correct answer because it is the primary element used in making pencils. The graphite core of a pencil is made by mixing powdered graphite with clay and a binder, and then encasing it in a wooden barrel. The use of lead in pencils is a common misconception, as lead was historically used in the past, but it has been replaced by graphite due to its toxicity.

Explanation
Silicon is a metalloid because it exhibits properties of both metals and nonmetals. It is a semiconductor, meaning it can conduct electricity under certain conditions but not as effectively as metals. Silicon is also brittle like nonmetals, but it can form alloys with metals. Additionally, it has a shiny appearance like metals. Therefore, silicon is classified as a metalloid.

Explanation
Michael Faraday is credited with discovering the principles of electromagnetic induction, which laid the foundation for the generation of electricity. He conducted numerous experiments and made significant contributions to the field of electromagnetism. Faraday's work led to the development of electric generators and transformers, revolutionizing the way electricity is generated and utilized. Therefore, he is considered the inventor of electricity.