Task: Question Answering
Input (English): Question: In an electrogravimetric analysis: 
 Options:  <1> The increase in mass of the electrode indicates the amount of analyte. <2> Current performance must be 100%. <3> A platinum mesh is always used as a working electrode. <4> A reference electrode is always needed. <5> The solution does not need to be conductive.
Output (English): 1