What are the five reasons palenontologists understand why fossils represent only a partial picture of the past?

An education expert is researching teaching methods and wishes to interview teachers from a particular school district. she randomly selects ten schools from the district and interviews all of the teachers at the selected schools. which type of sample did she use in this study? a)systematic sample b)probability sample c)stratified sample d)cluster sample

U.s. foreign aid incudes all the following programs excepta. humanitarian aidb. military assistancec. cycle of dependency grantsd. development aid

The physical feature that makes up part of the border between canada and the united states is the