- When you are sitting constant at bench your blood vessels and pressure of muscles are stable there.
- When you sudden wake up blood also wakes up .
- The gravity pulls it down from head.
- So you feel lightweight.
Muscular and nervous system involved
Answer : First, he should measure how long it takes for the liquid to become clear if X and Y are mixed together. Then, he should measure how long it takes if he also adds substance A to X and Y. He will find out if substance A is a catalyst
Explanation : Measuring the time taken for the liquid to become clear when X and Y were mixed together will give an assumption about the reaction time and the rate of reaction.
Then same measurement should be done when the substance A is added to the liquid of X and Y mixture. If there is a fast reaction that occurs when A is added to the reaction mixture then it can be concluded that A acts as an catalyst for mixing X with Y. Also, by comparing the reaction rates of both the reaction it can be easily concluded that A was a catalyst or not.
One way is for <span>a landowner to gather as much information as possible about his or her private water well, to know how it works, as well as who has had the land before them. The landowner needs to see if anyone has used pesticides in the area, as it can contaminate the well water. This is the most common way. The landowner can also check to see if any other chemicals have been spilt in the area or even a gas or oil leak, as that too can cause the contamination of well water.
I hope this helps.</span>