B. DNA is heated to separate strands
<span>First.PCR reaction</span>
Answer:
The three types of rocks are Igneous, Sedimentary, and Metaphoric.
Explanation:
<em>Igneous</em> rocks are formed out of melted rocks deep inside the Earth. A distinguishing unique characteristic is that they are hard.
<em>Sedimentary</em> is formed from layers of sand, silt, dead plants, and animal skeletons. A distinguishing unique characteristic is that they are easy to crumble.
<em>Metaphoric </em>are formed when minerals change through heat and pressure underground. Two distinguishing unique characteristics are that they may have many layers and are noticeably hard.
