Which of the following describes a relationship of mutualism?

a. a tapeworm latches itself in the intestines of a rat, feeding off all the nutrients eaten by the rat.
b. a polar bear catches a seal for dinner.
c. birds feed off the insects that are stirred up from the grasses as cattle move through.
d. oxpecker birds eat parasitic ticks off the backs of zebras

Chalk is an ionic compound. which is a property of all ionic compounds that makes chalkboard? particularly useful for writing on a a high melting point hardness and brittleness inability to dissolve in water a multicolored appearance

15 ! come and answer! a(n) is the general term for an infectious disease that has spread across a city, region, or country.

1. emigration the movement of people from one place to another 2. immigration a situation in which resources are being used up at a faster rate than they can be replenished 3. migration the leaving of one's homeland to settle in a new place 4. overpopulation the movement of people to a new country 5. sustainable development a situation in which the birth rate is not sufficient to replace the existing population 6. underpopulation the ability to meet current needs without reducing the ability to meet future needs 7. unsustainable development the increase in the population of a city 8. urbanization a situation in which the number of people exceeds the available natural resources in an area