B is the correct answer. They can sometimes show an extinction but not always.
Answer:
It's important to not touch the sides or the bottom of the test tube with the thermometer because touching it to the sides or bottom of the test tube fractures the glass and does not allow for correct temperature measurements.
Answer:
e) All of the answers are correct
Explanation:
The first X-ray picture of DNA taken in 1952 by Rosalind Franklin using the X-ray crystallography technique revealed the helical shape of DNA. Based on this discovery, it was discovered later on that the DNA molecule was made of two chains of nucleotides and at high humidity i.e when exposed to water it becomes long and thin.
I think the answer is either B or C, hope this helps! Sorry if it doesn't!
