You are my engineering assistant. Explain what's the reason behind of your answer for the given prompt(P) and the related question and answer pair (Q&A) below.

P: You are my engineering secretary. Answer the questions about the above document accurately by matching the dictionary FORMAT below. 
{"answer": "ANSWER",}The ion conductivity, who has unit of mS/cm or mS cm-1, is expressed with various expressions such as 'hydroxide conductivity', 'OH- conductivity', 'ionic conductivity', 'anion conductivity'
If the document has range of ion conductivity, only give the last value including its unit.
If the document has multiple values of ion conductivity, only give the maximum vlaue including its unit.
If the document has a value denoted by a multiplication sign, converts the value to a single numeric expression. For example, '1.54 × 10-2 mS cm-1' should be converted to '0.0154 mS cm-1'.
For the "ANSWER", extract the ion conductivity value including its unit. If there is no ion conductivity numerical value, write \'{"answer": \"-\"}\' without any other explanation for the "ANSWER"
you must not explain the additional explanations for the "ANSWER" except the value and unit.
Do not extract the value of ion-exchange capacity (IEC).
Q: A series of anion exchange membranes (4-QPPAF-TMA) were prepared by a metal-free, superacid-promoted polymerization reaction. The polymers were obtained with high molecular weight (Mn = 9.5-19.6 kDa, Mw = 44.9-622.5 kDa). 4-QPPAF-TMA membranes exhibited high hydroxide ion conductivity (up to 115 mS cm-1) at 80 °C, reasonable water absorbability (45% water uptake at 30 °C for 1.7 meq g-1), low to moderate dimensional swelling (5-15% at 30-80 °C for 1.7 meq g-1), and mechanical robustness (12.8 MPa maximum stress and 32% elongation at break for 1.7 meq g-1). Furthermore, 4-QPPAF-TMA membranes exhibited excellent alkaline stability in 8 M KOH at 80 °C for 1000 h, maintaining high conductivity (105 mS cm-1, 97% remaining). density functional theory (DFT) calculations suggested that the unique molecular configuration of the pendant ammonium head groups was responsible for high resistivity to the hydroxide ion attack. A fuel cell was operated with the 4-QPPAF-TMA membrane and an ionomer using a non-PGM cathode catalyst (Fe-N-C) to achieve a peak power density of 215 mW cm-2 accountable for 860 mW mg-1 Pt at a 590 mA cm-2 current density and 0.40 V (Pt-C cathode achieved 370 mW cm-1 at 810 mA cm-2 and 0.50 V). The fuel cell was operated at constant current density (15 mA cm-2) for 240 h with ?0.79 mV  Provide the entire answer in JSON format.
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