The substage condenser is either incorrectly positioned or the light stop is the wrong size for the objective- or there me be a smudge/mark on the eyepiece
Mortality, or death rate is a measure of the number of deaths in a particular population, scaled to the size of that population, per unit of the time. In this case a factor that would result to an increased mortality rate in a population due to increased competition of water will be the density-dependent factor.
Your answer would be $4 times $y.
Hope this helps; have a great day!
