scientists studying a population of a particular species of moth determine that the size of the population, N (in thousands), at time t weeks after the commencement of the study, can be modelled by the equation N= 2sin(pi(t)/5)+3, 0≤t≤40.

A) state the initial size of the population?

B) find the size of the population when it is a: i) minimum ii) maximum

C)what is the size of the population after 8 weeks? Give your answear correct to the nearest hundred.

D) on which day of the study does the population first exceed 4000 moths?

please help i understand them.