The genetic code of dna molucule is determind by a specific sequence of?

The genetic code is determined by the specific sequence of four nucleotide bases that make up DNA. The bases are guanine, adenine, thymine, and cytosine.

The answer is 80 years.
After 20 years, it will have an activity level of 2.
After 40 years, it will have an activity level of 1.
After 60 years, it will have an activity level of 0.5.
Then, finally, after 80 years the activity level will be 0.25 curie.