32. 6, 7. (a) What truths have we been helped to understand since the 1870 ’ s?
٦ ،‏ ٧ ‏ (‏ أ )‏ أَيُّ حَقَائِقَ نِلْنَا ٱلْمُسَاعَدَةَ عَلَى فَهْمِهَا مُنْذُ سَبْعِينَاتِ ٱلْقَرْنِ ٱلتَّاسِعَ عَشَرَ ؟‏