It's a hardness scale from 1-10 determining how easy or hard it is to scratch the mineral.
Remember that talc (like chalk or baby powder) is the softest and easiest to scratch then diamond being 10 is the hardest mineral to scratch or break or cut
Answer:
The last one, nicotine from tobacco
The interstellar medium is the matter as well as the radiations that are found in the galaxies occupying the spaces between the star systems.
Interstellar medium is mainly composed of hydrogen that is followed by helium and trace amounts of nitrogen, oxygen and carbon (considered traces when compared to amount of hydrogen).
Therefor, the right choice is:
<span>A. Water, Carbon dioxide, and Hydrogen</span>
Answer:
The value is 
Explanation:
From the question we are told that
The horizontal speed is 
The horizontal distance is 
Generally the time taken by the hot magma in air before landing is mathematically represented as

=> 
=> 
Generally the initial vertical velocity of the magma when it was lunched is

Then the final velocity of the magma when it hits the ground is mathematically represented s

Here the negative sign mean that the direction of the velocity is towards the negative y -axis
So

=> 