Name one way knife crime damages society
please I need help with a test

Mr. mann's science students were experimenting with speed. they set up a 1 meter (100 cm) track. the students used balls instead of cars. the balls were different sizes and made of different materials. four at a time, students rolled balls around the track to see which had the fastest and slowest speeds. some of their data are shown in the table. which ball will take the longest to complete one lap around the track?

Whether or not a given study has the possibility of causing harm to participants:

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