Problem:
On his crusade to rid the post-apocalyptic world of the Living Dead, a young Zombie Slayer named The Hermis was interested in finding the secret as to how the recently deceased was becoming reanimated. Many theories had circulated throughout the remaining civilized world (very little remained, just a couple of walled cities built in the desert to keep zombies out). However, no one was for certain what exactly caused the dead to walk the Earth. One theory did seem relatively positive. Prior to the world-wide epidemic, a satellite had crashed back to Earth carrying a large amount of radioactivity.
The Hermis had always felt there was a connection between the satellite incident and the Earth ravaged by 100's of thousands of flesh-eating freaks (that used to be your neighbors/friends/family/classmates).
The Hermis decided to do an experiment, he captured and killed 10 (n) Zombies (take out the head and the Zombie is destroyed). He had heard a report (prior to the TV networks going off the air) that the blood of the Zombies had carried a level of radioactivity that exceeded normal humans.
On average, the level of radioactivity was 198.2 gammas. The standard deviation was 3.3 gammas. The Hermis is 95% confident that the 10 zombies he has destroyed have at least 200 gammas of radioactivity in their blood.
Help The Hermis conduct his experiment and develop a confidence interval.