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Children begin to use tools at about what age? a. 18 months b. 2 years c. 1 year d. 6 months

An object weighs 40n in air , weighs 20n when submerged jn water and 30n submerged in a liquid of unknown density .what is the density of the liquid?

The procedures for reporting potential unanticipated problems involving risk to subjects or others to the irb are: stated in the human subject protection regulations, but not in the drug or device regulationsincluded in the consent processdetermined by research staffdetermined by the institution in its written policies and procedures