River valley trade made them key economic areas.
Hope this helped. :)
Answer:
Rocks found on different mountains are different ages.
Explanation:
Radiometric dating of rocks and fossil records gives scientists an idea of the timelines of certain organisms. Fossils of long dead species found in different strata of rocks can be used to speculate the age and changes these organisms have experienced overtime.
Fossils found in the uppermost strata are indicative of organisms that died not quite long whereas fossils found in lower layers are indicate of organisms that died a long while ago. These studies also provide insight into the changes that the earth has experienced overtime.
Answer: A - P.M. Grootes, K.M. Cuffey, and J.M. Bolzan, among others.
Explanation: Dr. Anandakrishnan collaborated and coauthored with all of the people listed above and has worked with many other people.
During the year 1994, Dr. Sridhar Anandakrishnan collaborated with Kurt M Cuffey, Richard B Alley, Pieter M Grootes and John M Bolzan on the topic 'Calibration of the δ18O isotopic paleothermometer for central Greenland, using borehole temperatures'
They calibrated the δ 18O paleo-thermometer for central Greenland using borehole temperatures, a thermal model forced by a measured δ 18O record and a formal inverse technique. The calibration is determined mostly by temperature fluctuations of the last several centuries, including the Little Ice Age.
Results are generally insensitive to model variables, including initial condition, basal boundary condition, parameterization of snow thermal properties, ice thickness and likely errors in temperature and isotope measurements. Results of this borehole calibration also seem to be in agreement with modern spatial gradients of δ 18O and temperature.
They suggest that calibrations of isotopic paleothermometers using borehole temperatures are a useful paleoclimate tool because they are independent of spatial gradients and include the effects of prehistoric temperatures.
Answer:
C. The best alternative given up
Explanation:
I don't see any underlined word but If the word is benifit, then i think that is that answer. I apologize if it is wrong.
