The time period being referred to is the sensitive period. This time period is also referred to as the critical period. The importance of a critical period is such that it must involve certain stimuli from which an organisms learns and acquires traits. If some of these stimuli are not present in the critical period, the organism has difficulty acquiring the trait or skill, and may even find it to be impossible to learn the skill.
All you have to do is take the CGR (capita growth rate) percentage you just found and divide it by the number of years, months, etc. The complete formula for annual per capita growth rate is: ((G / N) * 100) / t, where t is the number of years.
As for this problem, the most probable answer and the most likely answer for this one would be D. the effect of pesticides on organisms in the environment.
A toxicologist would only study about chemicals and their effect on organisms in the environment. Pesticides are chemicals made to combat organisms that aren't wanted particular parts of the environment such as crops and rice field. These pesticides don't just affect those organisms that are targeted, but even the users and other organisms that may have come in contact with pesticides.
First of all, the most common type of CNS neuron is the multipolar neuron meaning it has many dendrites and dendritic branches, a cell body or soma, and a single axon. The information flow through this neurons starting from receiving multiple impulses from multiple synapses since this kind of neurons has many dendrites. The signal will then flow in an anterograde manner meaning the multiple signals will flow towards the cell body or the soma to be integrated. Next is that the integrated signal will flow to the neuron's axon to be transmitted to other neurons.