Usually the average growth cycle of eyebrows is 5 to 7 weeks, but it can be shorter or longer depending on various factors such as, your age, metabolism, and weight.
B, both chemical and biological factors are involved
During complex and demanding tasks, teens distribute the workload evenly throughout the brain. In teenagers the prefrontal cortex is still developing and therefore they may rely on a part of the brain called the amygdala to make decisions and solve problems more than adults. The prefrontal cortex communicates with other sections of the brain through connections called the synapses.
