<span>The elements that are found in a high proportion in Earth's crust are oxygen, aluminium, iron, calcium, potassium, sodium, and magnesium. But for your Option, I think it is B) Oxygen and Silicon. This is because Oxygen makes 46.6% while Silicon makes 27.7% of the Earth crust.</span>
5. System level
6. Organ level
<u>Answer:</u>
<em>A constant is something whose value cannot be changed and is used for comparison purpose. </em>
<u>Explanation:</u>
The controlled variable is a type of variable whose value is kept constant during the experiment to get the desired or expected result. The difference between constant and a control variable is that the constant can never be changed.
However, the value of control variable can be changed but is kept constant with a purpose in an experiment to get the data. The controlled variable in a battery can be the multi meter that should be used for all the batteries.
Certified answer cred due to :
brainly.com/profile/HistoryGuy-343799One way in which classification is used at school is the separation of different subjects and subject materials. For instance one day you may go to a math class, while another day you may go to a french class.
Answer:
54
Explanation:
162 divided by 3 is 54
and right on khan academy
