Chapter 1.1, Problem 3P

At $11:09\text{}\text{}\text{p}\text{.m}\text{.}$ a forensics expert arrives at a crime scene where a dead body has just been found. Immediately, she takes the temperature of the body and finds it to be ${80}^{\circ }F$. She also notes that the programmable thermostat shows that the room has been kept at a constant ${68}^{\circ }F$ for the past $3$ days. After evidence from the crime scene is collected, the temperature of the body is taken once more and found to be ${78.5}^{\circ }F$. This last temperature reading was taken exactly one hour after the first one. The next day the investigating detective asks the forensic expert, “What time did our victim die?” Assuming that the victim body temperature was normal ( ${98.6}^{\circ }F$) prior to death, what does she tell the detective?