I know that we can find how old the Earth is by knowing how much uranium ultimately decayed into lead. Uranium-238 has a very long to decay, about 4.5 billion years. So that is how we are able to understand how old the Earth is.
Answer and Explanation:
How to Calculate the Percent Abundance of an Isotope
Step 1: Find the Average Atomic Mass. Identify the atomic mass of the element from your isotopic abundance problem on the periodic table. ...
Step 2: Set Up the Relative Abundance Problem. ...
Step 3: Solve for x to Get the Relative Abundance of the Unknown Isotope. ...
Step 4: Find percent abundance.
The answer is B. Commensalism.
<span>Commensalism is a relationship between two organisms in which only one of them has benefit, and the other one is not affected. In this example, the Great Burdock's plants spread their seeds using animals, so they benefit from this relationship. On the other hand, animals neither have benefits not are harmed from the relationship.</span>
When it comes to ecosystems, a mountain, a river, and a cloud have more in common than you might think. Abiotic factors have specific and important roles in nature because they help shape and define ecosystems.
Biotic and Abiotic Factors
An ecosystem is defined as any community of living and non-living things that work together. Ecosystems do not have clear boundaries, and it may be difficult to see where one ecosystem ends and another begins. In order to understand what makes each ecosystem unique, we need to look at the biotic and abiotic factors within them. Biotic factors are all of the living organisms within an ecosystem. These may be plants, animals, fungi, and any other living things. Abiotic factors are all of the non-living things in an ecosystem.
Both biotic and abiotic factors are related to each other in an ecosystem, and if one factor is changed or removed, it can affect the entire ecosystem. Abiotic factors are especially important because they directly affect how organisms survive.
Examples of Abiotic Factors
Abiotic factors come in all types and can vary among different ecosystems. For example, abiotic factors found in aquatic systems may be things like water depth, pH, sunlight, turbidity (amount of water cloudiness), salinity (salt concentration), available nutrients (nitrogen, phosphorous, etc.), and dissolved oxygen (amount of oxygen dissolved in the water). Abiotic variables found in terrestrial ecosystems can include things like rain, wind, temperature, altitude, soil, pollution, nutrients, pH, types of soil, and sunlight.
The boundaries of an individual abiotic factor can be just as unclear as the boundaries of an ecosystem. Climate is an abiotic factor - think about how many individual abiotic factors make up something as large as a climate. Natural disasters, such as earthquakes, volcanoes, and forest fires, are also abiotic factors. These types of abiotic factors certainly have drastic effects on the ecosystems they encounter.
A special type of abiotic factor is called a limiting factor. Limiting factors keep populations within an ecosystem at a certain level. They may also limit the types of organisms that inhabit that ecosystem. Food, shelter, water, and sunlight are just a few examples of limiting abiotic factors that limit the size of populations. In a desert environment, these resources are even scarcer, and only organisms that can tolerate such tough conditions survive there. In this way, the limiting factors are also limiting which organisms inhabit this ecosystem.
Answer:
C. Covalent Bond
Explanation:
A covalent bond is a chemical bond that involves the sharing of electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs, and the stable balance of attractive and repulsive forces between atoms, when they share electrons, is known as covalent bonding.
