The doctor took the temperature of a dead body at 11.30 Pm which was `94. 6^@F`. He took the temperature of the body again after one hour, which was `93. 4^@F`. If the temperature of the room was `70^@F` , estimate the time of death. Taking normal temperature of human body as `98. 6^@F`. [Given: `log(143/123)=0. 15066 ,log(123/117)=0. 05` ]