Answer:
C : 1953
Explanation:
The discovery in 1953 of the double helix, the twisted-ladder structure of deoxyribonucleic acid (DNA), by James Watson and Francis Crick marked a milestone in the history of science.
Answer:
A physical quantity is a property of a material or system that can be quantified by measurement.
Chloroplasts are where photosynthesis occurs, so maybe that's a hint to know which cells have chloroplasts.
I think the best choice to fill in the blank would be disengagement. It is a theory in aging that perceives aging as an inevitable occurrence which results in decreased social interaction between the people in the society and the person. Hope this helps.
