Answer: The correct option is 3.
Explanation: We are given a compound which is made up of iron and oxygen only. The ratio of the two are given as:
This means that, number of iron ions are 2
Number of oxide ions are 3
From the above information, the formula becomes : 
The valency of iron = 3
Valency of oxide = 2
This compound is named as iron (III) oxide.
Hence, the correct option is 3
Answer:
a)22.2°C after adding magnesium
b)17.3°C before adding magnesium
c) 4.9 is change
Experimental errors occurs in the execution of experiment design. Example of experimental errors are mistakes in data entry, systematic error, and random error caused by environmental conditions. Did you even heard about type I and type II error? Because that may be the 2 ways you are looking for.
A false positive is called a Type I error, and it is the type of error that incorrectly rejecting the null hypothesis in the favor of the alternatives.
A false negative is what you called Type II error, it is the opposite of type I error and it is the false acceptance of the null hypothesis. A type II errors are not seen to be as problematic as type I error, type I error is more serious than type II error, because you have wrongly rejected the null hypothesis.
Answer:
Mitochondria are the structures within cells that produce energy.
Explanation:
Mitochondria are also like the human digestive system because the digestive system breaks down food to supply the body with energy like the mitochondria breaks down food to supply the cell with energy.
Answer:
One CME is produced every five days
Explanation:
