At any given time, one (1) billion tons of phytoplankton can be found. Every year, around 45 billion tons of phytoplankton exist in the ocean. Beyond serving as a food source for fish, they play a vital role in the carbon cycle. This phytoplankton absorbs 45–50 billion tons of inorganic carbon into their cells, representing the principal source of atmospheric oxygen.
Answer:
Various brands of nail polish utilized by Sarah.
Explanation:
In conducting an experiment, two variables are assessed; these are the independent variable and the dependent variable. The variable that is altered consistently to observe its effects is identified as independent variable while the one under examination is termed the dependent variable.
In this scenario, Sarah aims to determine which nail polish brand lasts longest without chipping. Thus, the diverse brands of nail polish she experiments with are designated as the independent variable.
The "passenger pigeon" was once the most prevalent bird in North America, with populations soaring to around 3 billion. They typically traveled in large flocks. Their decline began in the 19th century as they were hunted for food due to their affordability and taste. Additionally, they served as a valuable protein source and were easy to capture because of their numbers despite their fast flight. Some were killed to prevent crop damage, and their nesting habitats faced disturbances, leading them to leave forests. Over-hunting, exacerbated by technological advancements, resulted in more pigeons being killed than were being born, leading to their extinction, with the last one dying in 1914.
