152. The total number of casuafties and the extent of material damage that are the result of one nuclear explosion may vary rridely depencling on a number ofAl35 /39? Ens_L1Sn Annex factors ' sone of which are not fully understood. According to one source f3/ tneHiroshima bomb, estimated to be 13 kt., caused the death of about TO,OO0 civiliansvithin a month, and some further 8O,O0O were injured. A larger lolrl, ee tt.,against Nagasaki gave easualties of J+O,OOO and 20,000 coffespond.ingly. Thediscrepancy between the tvo outcones has been ascribed to th; diff;rent topographiesof the tffo cities. fn Nagasaki there are a number of ridges separating differentparts of the city, which 1ead. to a fower average popufation aenlity .ni to "o." weakening of the air brast in certain areas. within the r ran. -radius from ground-zeao, however, the casualties (dead and inJured) vere about 95 per cent of the totafpopulation in both cases, with a sonewhat higher incidence of fatalities inNagasaki "
**Analysis**
The text appears to be discussing the consequences of nuclear explosions, specifically the number of casualties and material damage caused by the atomic bombings of Hiroshima and Nagasaki. The text mentions the topography of the cities, the radiation effects, and the number of deaths and injuries. This suggests that the text is more closely related to the field of science, specifically physics and radiation, rather than economics or other social sciences.

**Category**
Health, Science and technology