1) yes, a green toe is unnatural and dangerous.
2) She may have skin cancer.
3) Depending on whether the mutation took place on the dominant or recessive gene, and what the father's gene is (dominant or recessive), the child may or may not have it.
Answers:
a. We will see DNA fragments with 145-200 bps (only one band)
b. The DNA sequence linked to histones will be protected from the action of DNase I, thereby this enzyme only can cut linker DNA (i.e., 55 bp fragments). In consequence, it is expected to observe a single band with a length of approximately 145 to 200 base pairs