Hello!
An initial observation is the first thing a scientist notices about a topic before conducting the experiment. We can see that it is the first thing in the paragraph in this case, that dandelions grow as unwanted weeds in many lawns.
The hypothesis is the guess about the result of an experiment made before the experiment is conducted. In this case, it is that a weed killer (Killimal) would kill all the dandelions while leaving the grass healthy. This is not specifically a guess made by the scientist, but more like a prediction he wanted to verify.
An independent variable is the variable being changed in the experiment by the scientist. Here, it is whether Killimal was sprayed or not.
The dependent variable is the variable being measured, and the one being affected by the independent variable. His observation would be whether the grass and dandelions would be killed. This is because the weed killer would be directly affecting whether or not these would be killed.
The control variables are ones which are kept the same in the experiment as to not interfere with the final results. In this case, it would be the density of dandelions, the amount of sunlight, and the amount the plants were watered. These were kept exactly the same, as they could've affected the dependent variable if changed.
The control group was the one that is not impacted by the independent variable. The control group makes sure that it actually is the independent variable affecting the dependent, and it isn't some outside unknown variable. This would be the plot without the Killimal.
The experimental group is the one being experimented on from the independent variable. This would be the plot with the Killimal.
Hope this helps!
Answer:
vaccination
Explanation:
The vaccination has been one of the most revolutionary inventions in the medical field. This invention helped protect people from numerous diseases, some being totally neutralized, while some having only minor effects on the human body. The vaccination basically is a way of enhancing the immune system of the body by injecting in it a weakened form of the pathogen. In this way, the weakened form of the pathogen is not capable to harm the body, and the body is not fighting against it, but instead the pathogen becomes part of the body and its defense mechanism, so when the pathogen strikes, the body has a counter attack and defeats it.
Answer:
All of these are correct
Explanation:
According to the question, marble is a rock formed from limestone, which in turn is also formed from Calcite. This shows that marble is a kind of metamorphic rock because a metamorphic rock is any rock that is formed by the alteration of other rocks caused by heat, pressure or chemicals etc. These changes that occurs in the previously existing rocks are called METAMORPHOSIS.
Hence, since marble is formed from limestone, it concludes that marble is a metamorphosed rock formed from a previously existing limestone rock. Also, since Calcite, a precursor of limestone that marble is formed from can be degraded by acids, both limestone and marble which are formed from it will also be dissolvable by acids.
Chage identity of a substance
