Which of the following always exist between two objects having mass ● elastic force ● contact force ●gravitational force ●magnetic force

Which is an advantage to using nonrenewable resources? a. they can be cheaper. b.they can have a lower impact on the environment. c.they can be used up rapidly. d.they can contribute to global warming.

Assessment includes a. interviews, recorded conversations, videos, frequency counts, and time samples. b. formal standardized tests and developmental screening tools. c. various types of documented observations, documentation of child work, checklists, rating scales, and standardized tests. d. anecdotal notes, narratives or daily records, daily health checks, and teacher observation checklists.

Ben is interested in using a source that provides original research, current and developing trends and experts within specific fields. which source should he use?