Answer:
Neogene period is almost 31% of Cenozoic area.
Explanation:
Cenozoic era exists between 66 mya and zero mya. However, Neogene period existed between 23 mya to 2.6 mya. The difference is 20.4 mya.
To calculate the percent of neogene,
= (20.4/66) x 100
= 30.9%
Therefore, Neogene was approximately 31% of total Cenozoic era.