18. <em>Penny</em>: Used to measure mineral toughness; <em>Cuprum</em> penny's toughness is 3.
<em>Hand Lens</em>: Could be used to measure the hardness of the mineral; the glass can be used as a scratch platform; it can also be used to test the luster of the mineral tile; the mineral is rubbed in the glass portion of the tile and a powdery strike of the stone is given to distinguish the colour of the rock.
<em>Geological hammer</em>: Used to break down the mineral to assess whether or not it has cleavage, and to detect fractures
<em>Pocketknife</em>: Used to define mineral tenacity; the tenacity of the mineral can be silky, malleable, sectile, elastic, or flexible.
17. Volcanoes are holes or cracks in the lava-flowing crust of the earth. They are normally placed on the borders of tectonic plates as they are created as the plates clash and create gaps. In other words, volcanoes located at convergent-plate boundaries.
I am joyous to assist you anytime.
I believe this difference in concentration of dissolved Particles from one location to another is called a concentration gradient.
Yes. RNA is single stranded
true
Explanation:
messages from the nervous system cause these muscular contractions
DNA replication is a process in which two copies of DNA which are duplicate of each other are formed from original one so <span> the event that will follow DNA replication in a cell cycle is
</span><span> Chromosome duplication
</span>because by this new genetic material is produced and it is also defined as duplication of the gene containing region of DNA
so i conclude option B is correct
hope it helps