以真空吸引娩出胎兒,較適合的壓力大約是多少kg/\mathrm{cm}^{2}?
\mathrm{cm}^{2}
0.2 kg/\mathrm{cm}^{2}
0.6 kg/\mathrm{cm}^{2}
1.0 kg/\mathrm{cm}^{2}
2.0 kg/\mathrm{cm}^{2}