In a laboratory population of $40$ fruit flies, if $4$ flies die in a week, what is the death rate?

If natality is represented by $B$,mortality by $D$,immigration by $I$,emigration by $E$,and population density by $N$,then the population density at time $t+1$ is represented by:

The population will be of declining type if the number of individuals in . . . . . . .

Population density of terrestrial organisms is measured in terms of individuals per

The abundance of a species population within its habitat is called

If there were $30$ lotus plants in a pond last year and through reproduction $10$ new plants were added, taking the current population to $40$, then the birth rate = $.........$ offspring per lotus per year.