About three billion years ago, single-celled organisms called cyanobacteria lived in earth’s oceans. they thrived on the ocean’s abundance of , which they used during the process of photosynthesis. much later, this process allowed organisms, such as fish, to survive by extracting dissolved from ocean waters. a. oxygen b. carbon dioxide c. nitrogen

The first blank is carbon dioxide, second one is oxygen

answer

procedural programming, object-oriented programming

explanation

procedural programming is a type of computer programming language that specifies a series of well structured steps and procedures   within its development period of time. it contains a systematic order of statements, functions and commands to complete a computational task or program. it is centered on creating procedures. while object oriented programming is a programming language that is centered on creating objects rather that actions and data rather than logic.. it has four principles which are inheritance, polymorphism, abstraction and encapsulation