Name the two types of twins and describe how they are formed.

Hepatitis b and hiv/aids are two serious infections that can be transmitted by a. breastfeeding and contact with blood. b. sharing food and sharing drinks. c. transmission by air, water, and shared bodily fluids. d. skin contact, contact with urine, and sharing clothing.

In a study of a weight loss program, 40 subjects lost a mean of 3.0 lb after 12 months. does the weight loss program have practical significance? a. yes, because the weight loss program worked and the subjects lost a mean of 3.0 lb. b. no, because the mean weight loss of 3.0 lb after one year does not seem to justify the program. c. no, because the sample of 40 subjects was too small to determine if the program was useful. d. yes, because the mean weight loss of 3.0 lb after one year does seems to justify the program.

Which of these is a sexual stereotype? a) on average, males are taller than females. b) people over the age of 60 are not interested in sex. c) male hormone levels differ from those of females. d) there are more male representatives than female representatives in congress.