Students in mr. klein’s chemistry class are conducting an experiment to calculate the specific heat of a copper sample. mr. klein requires each lab team to repeat the experiment until their percent error is 2% or less. percent error is calculated using observed values (those students calculate from their lab results) and the true value (the accepted value based on reference). the formula for percent error is:
(observed – true) x 100
true
if the accepted value for the specific heat of copper is 0.385 j/g°c, which of the following lab
teams have an unresolved problem on their hands?
a.
team 1: calculates 0.390 j/gºc
b.
team 2: calculates 0.395 j/gºc
c.
both teams
d.
neither team

Alaska and northern canada have a diet rich in vitamin d and their skin color is darker than predicted on the basis of iv intensity at their latitude. explain the observation:

Which is an important function of normal flora? a. aid with bone marrow production. b. crowd out pathogenic bacteria. c. destroy digestive track pathogens. d. manufacture iron in the bloodstream.

Archeologists have discovered three sites showing conclusive evidence for the mastery of fire in tanzania, from a period slightly after the time that homo habilis was present in africa. these sites clearly were founded by homo erectus, the descendent species of homo habilis that migrated north, out of africa and into asia. homo erectus was known to have mastered fire, from ample evidence at sites in asia. there is no reason to attribute mastery of fire to homo ergaster, the descendent species of homo habilis that remained in africa.which of the following is an assumption on which the argument depends? (a) before their migration, homo erectus occupied african territory as far south as tanzania.(b) the strain of migration provided the selective pressure motivating homo erectus‘ mastery of fire.(c) homo ergaster would not have derived as much benefit from the mastery of fire as did homo erectus.(d) homo ergaster inherited all cultural knowledge from homo habilis, a species that did not have mastery of fire.(e) homo ergaster did not occupy regions as far south as tanzania until well after the time of these three sites.