Question

the number of individuals of a species per unit area or volume of habitat is:
a carrying capacity
b a community
c a volumetric sample
d population dynamics
e population density

question 4
conditions whose growth - limiting effects increase as a population grows:
a are density - independent factors
b are density - dependent factors
c include competition for needed resources
d are density - dependent factors which includes competition for needed resources

Explanation:

For Question 1: The definition matches population density (individuals per unit area/volume).
For Question 2: Density-dependent factors have growth-limiting effects increasing with population size, and competition is a key example.

Answer:

Question 1: E. Population density
Question 2: D. Are density-dependent factors which includes competition for needed resources