Gemma is taking photos with her camera using autofocus. In order to get the camera to automatically focus on the subject so that she can review this before actually taking the photo, what should Gemma do

the answer is b, have negligible mass

float.

archimedes' principle

denser than water sinks in water.

denser than mercury would sink in it

blue light is scattered in different directions by the tiny molecules of air. blue is scattered more than other colours because it has a shorter distance to travel which results in smaller waves. this is why we see a blue sky most of the time.