Refer to the Radiation Protection Dosimetry (Dec. 2010) study of radon exposure in tombs carved from limestone in the Egyptian Valley of Kings, Exercise 7.39 (p. 362 ). The radon levels in the inner chambers of a sample of 12 tombs were determined, yielding the following summary statistics: x̅=3,643  Bq / m^3 and s=4,487  Bq / m^3. Use this information to estimate, with 95 % confidence, the true standard deviation of radon levels in tombs in the Valley of Kings. Interpret the resulting interval.

Radiation background of the settlement in the area of the Chernobyl zone. The dosimetry in the chemical protection cloak measures the radiation level in an abandoned rural home.