Radioactive substance A breaks down to substance B with a half-life of 1,000 years. If we start out with four kilograms of radioactive substance A, how much of those four kilograms of substance A will remain in 3,000 years?
A) 250 grams
B) 500 grams
C) 1 kilogram
D) 2 kilograms
Question 2
Radiation exposure immediately around a properly functioning nuclear power plant is about
A) 1 greater than the normal environmental background exposure.
B) double normal environmental background exposure.
C) 10 times higher than normal environmental background exposure.
D) 100 times higher than normal environmental background exposure.