Answer:
A. A scientist investigates a mouse's growth in nature by watching the animal.
A field study is a raw collection of data, typically in the natural habit of the organism; hence why an experiment taken in a lab isn't a field study.
 
        
             
        
        
        
Answer:
<em> 14, 508J/K</em>
ΔHrxn =q/n
where q = heat absorbed and n = moles
Explanation:
<em>m = mass of substance (g) = 0.1184g</em>
1 mole of Mg - 24g
<em>n</em> moles - 0.1184g 
<em>n = 0.0049 moles.</em>
Also, q = m × c × ΔT
<em> Heat Capacity, C of MgCl2 = 71.09 J/(mol K)</em>
<em>∴ specific heat c of MgCL2 = 71.09/0.0049 (from the formula c = C/n)</em>
<em>= 14, 508 J/K/kg</em>
ΔT=  (final - initial) temp = 38.3 - 27.2
= 11.1 °C.
mass of MgCl2 = 95.211 × 0.1184 = 11.27
⇒ q = 11.27g × 11.1 °C × <em>14, 508 j/K/kg </em>
<em>= 1,7117.7472 J °C-1 g-1</em>
<em />
<em>∴ ΔHrxn = q/n</em>
<em>=1,7117.7472  ÷ 0.1184 </em>
<em>= 14, 508J/K</em>
 
        
             
        
        
        
Answer:
1.225g
Explanation:
From the question given, 
Volume of diamond = 0.35cm^3
Density of diamond = 3.5g/cm^3 
Mass of diamond =?
Density = Mass /volume
Mass = Density x volume 
Mass = 3.5 x 0.35
Mass of diamond = 1.225g
 
        
             
        
        
        
Answer:
The early atmosphere
Its early atmosphere was probably formed from the gases given out by volcanoes. It is believed that there was intense volcanic activity for the first billion years of the Earth's existence. The early atmosphere was probably mostly carbon dioxide, with little or no oxygen.
Explanation:
Hope this helps! Brainly if so!