Answer:
The fourth plant that receives pure water is the control group.
Explanation:
The election of a control group is essential in an experiment. Its principal purpose is to allow the discrimination of the results obtained by the treatment in the study, in this case, <em>the different concentrations of salty water that each plant receives</em>. The control group provides a reference point. It must be selected from the same population of the treatment groups. Both groups must be similar in every variable that might influence the results, <u>except for the study treatment.</u>
Answer:An increase in light intensity causes both pupils to contract (see iris) even if only one retina is directly stimulated. This is known as a consensual reflex. Conversely, a decrease in light intensity causes dilation of the pupils
Explanation:
The decay of uranium isotopes is used to provide information about the age of Earth.
<h3>
Explanation:</h3>
Isotopes of Uranium U-232, U-233 , U-234 , U-235 , U-236 , U-238 are used as fuel in nuclear reactors or as explosives for nuclear weapons. Uranium 238 is not very radioactive and it constitutes for nearly 99.3% of natural uranium on Earth and has the longest lifetime: its period is 4.5 billion years, about the age of Earth.
Use of radiometric dating techniques help in defining the age of substances (natural or man-made) using the known decay rates of radioactive elements. Each element has an individual decay rate and half life time.
Two Uranium isotopes (U-238 and U-235) are used for radiometric dating. Both the isotopes have different decay rates and half life period. Both are unstable and radioactive. Since two different isotopes produce two different decay clocks (one as a reference to other), it is beneficial in accurately determining the age of samples. The age of earth (rocks or other natural elements) can be easily determined using Uranium isotopes.
the answer is A. covalent bonds
Hello!
The 4 major earth science fields are:
Geology: It Is the Study of the composition and internal structure of the planet. A Geologist would examine the earthquakes.
Oceanology: It is the Study of the seas and oceans, and everything related to it. An Oceanologist would examine the large waves to shore and the major flooding.
Meteorology: It is the study of the dynamics of the atmosphere of the Earth. A Meteorologist would study the cooler weather.
Astronomy: It is the study of the celestial bodies of the Universe. An astronomer would examine the meteor impact by itself.
