In mid-ocean ridge areas, ocean water is cycled through the crust because of the high heat flow in the area. Water in the rock is heated over the magmas, rising up and drawing in cold water from the sides. This process is occurring all over the world, and is the primary means for maintaining ocean salinity in a relatively constant range over the long term, as elements in the sea water when it is heated react with the rocks. There is so much water flow, cumulatively over the entire world, that this process basically buffers ocean chemistry.
Obviously large increases or decreases in salinity can and do occur in isolated basins that do not have free exchange with the open oceans.
Answer:
Argon
Explanation:
Argon is actually used to determine the age. It's called potassium-argon dating b/c when volcano erupts the rocks in it contain potassium. The potassium slowly decays and produces argon. Scientists measure how much argon is in a given volcanic rock and do math backwards to figure out how many potassium atoms were needed to produce the given amount of argon. We already know the rate at which potassium decays so then they put two and two together to find the age.
Here's a link with some cool info on it:
https://divediscover.whoi.edu/archives/hottopics/volcano.html
What makes studying people difficult is that you are yourself. You will always be different from other humans, so studying them naturally takes you out of your comfort zone
Chloroplast, sorry I'm a little late