Answer:
"1.4 mL" is the appropriate solution.
Explanation:
According to the question,
Now,
Increase in volume will be:
⇒ 
By putting the given values, we get
Lithium i believe is the answer
Spectrophotometric cell or a cuvette is made of quartz for UV spectrophotometers. These cuvettes are used as sample holders for the spectrophotometric determination of the analytes. The material that makes up the cuvette and the condition of the cuvette is to be taken care of in order to avoid erroneous absorbance readings. The sample holder or the cuvette must be removed from the spectrophotometer in between two successive readings. This is to ensure that the light sensing detector of the instrument is not affected.
