Which of the following represents a difference between rna and dna?
a
none of these are correct
b
dna contains the base thymine and rna contains the base uracil
c
rna contains the sugar deoxyribose and dna contains the sugar ribose
d
dna is single stranded and rna is double stranded

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

In "the man in the water," what was the remarkable occurrence that rosenblatt reported?

Creating new things to solve problems and improve life depends on the close interaction of which two fields?