This one can be tricky, because your are changing the appearance of the substance. But here, you aren't changing its chemical form, so its a physical change. Even though you can't bring the pencil to its original beginning, its still a physical change.
Answer: Physical change.
B only in the nucleus and rough ER
Answer:
It could lead to several later problems in the cell.
Explanation:
Removing a piece of DNA could severely affect the cell but it could also cause nothing. Depending on the part that is damaged, it could codify for a vital protein but it could also be an intron, which are pieces of DNA that don't codify for any protein. This has been recently researched and even though there are introns that could cause some serious trouble, most of them are an unknown matter to nowadays scientists. Anyway, a wrongly repaired sequence could end in a mutation that can potentially damage the cell and therefore the organism.
