At the End of Which of the Following Periods Did

question 121

Multiple Choice

At the end of which of the following periods did oxygen concentrations decrease from about 30 percent to 15 percent?

• A) Cambrian
• B) Cretaceous
• C) Permian
• D) Devonian
• E) None of the above

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Definitions:

Operating System

Software that manages computer hardware, software resources, and provides common services for computer programs, acting as an intermediary between users and the computer hardware.

Kernel Panic

A critical system error that the operating system cannot recover from. When this happens in macOS, the Mac reboots to return to a stable state.

Kernel

The heart of an operating system, which acts as the controller and interpreter for nearly everything in a system so that hardware and software can interface and work together. It controls memory management, peripherals, and allocating other system resources to processes.

Spotlight

A macOS universal search tool that can locate every file and directory and also search email, contacts, music, and even the web.