Complex sentence: Ben Kiernan estimates the total number of victims at between 50 and 150 thousand; a demographic study by Marek Sliwinski estimated 40,000 Cambodians were killed by the bombing, though it did not distinguish between civilians and combatants.
Split into simpler sentences: Ben Kiernan estimates the total number of victims at between 50 and 150 thousand. A demographic study by Marek Sliwinski estimated that 40,000 Cambodians were killed by the bombing, though it did not distinguish between civilians and combatants.