Which statement is correct about the conclusions of historical events? a) historical event conclusions can be tested using the scientific method. b) historical event conclusions are repeatable. c) historical event conclusions are limited to evaluating existing evidence. d) historical event conclusions can be observed in a laboratory setting.

C is the correct answer I believe

Historical event conclusions are limited to evaluating existing evidence.

Explanation: Historical events can be best understood by the examining the evidences discovered from different sites. That evidences may be present in the form manuscripts, literature, etc. And sometimes it is present in the form of fossils. Radio carbon dating is used to determine the age of such fossils which tells us about various conditions of that time when we examine it.

"you start with 15.67 g mgco3-xh2o, when heated and all the water is removed, you are left with 7.58 g mgco3 only.

therefore, you had 15.67 - 7.58 = 8.09g h2o  

moles of each :

7.58g mgco3 = ? moles = 7.58g / 83.4g/mole = 0.09moles  

8 09g h2o = ? moles = 8.09g / 18g/mole = 0.44moles  

molar ratio between the two by dividing both numbers by the smallest number :

0.09 / 0.09 = 1  

0.44 / 0.09 = 4.8  

mgco3-5h2o"