When 100mL of HCl are added, the pH of the solution will equal 7. Bromthymol Blue, an indicator which changes color in the 6-8 pH range is used in this case, because we can see when the pH is equal to 7.
Firstly, you have more chance of getting hit by a car or killed by a coconut falling on your head than getting attacked by a shark. A shark isn't going to pick you by what colour your boogie board is. Usually they attack people who have just gone to the toilet or are simply the unlucky ones. I think Mythbusters found that sharks are not attracted to certain colours but they tend to bite the colour yellow more once they do attack.
FACT: Sharksâ eyes, which are equipped to distinguish colors, employ a lens up to seven times as powerful as a humanâs, and some shark species can detect a light that is as much as ten times dimmer than the dimmest light the average person can see. MYTH: Most species of sharks are dangerous to people.