Consider these maps from the set of students in a discrete mathematics class. under what conditions is the map injective if it assigns to a student his or her
a) mobile phone number.
b) student identification number.
c) final grade in the class.
d) home town.

Which factors slowed population growth in china until the 1300? a. one child policy. b. urbanization c. epidemics. d. warfare

According to the federal regulations, which of the following studies meets the definition of research with human subjects? a study of twenty 4th grade classrooms in which researchers ask the schools to systematically vary the time of day reading is taught, and collect weekly assessments of reading comprehension for each child over a three-month period.the collection of data, by a playground designer hired by the superintendent of schools, about the physical dimensions of school playgrounds, presence of fencing, and the kinds of equipment currently provided.a feasibility study for implementing a year-round school program, focusing on economic issues such a facilities utilization and transportation costs.an analysis of aggregate data comparing statewide high school graduation rates provided by the state department of public instruction, using county tax information.

Ateam of men and women of different ethnic backgrounds, age, and physical capabilities work for a tv show which involves decorating gardens in a very short time frame. the team worked in co-ordination to come up with new decorative ideas for each episode. this is an example ofa team of men and women of different ethnic backgrounds, age, and physical capabilities work for a tv show which involves decorating gardens in a very short time frame. the team worked in co-ordination to come up with new decorative ideas for each episode. this is an example of