Tutor profile: Tyler J.
Subject: Python Programming
What is your favorite programming language?
Python is my favorite language because of it's simplicity, but power allows for it to have many uses beyond what could have once thought were possible with it. There are so many libraries available for it.
Subject: Environmental Engineering
Define and explain the difference between LNAPL and DNAPL.
LNAPL stands for Light non-aqueous phase liquid, such as gasoline. It is less dense than water therefore it tends to float at the top of an aquifer. DNAPL stands for Dense non-aqueous phase liquid, such as dry cleaner solvents. It is more dense than water and therefore it tends to "sink" in the aquifer. It would be found at highest concentrations typically at a confining layer (such as clay) where the plume will spread out. The difference between these two types of contaminants is important with determining where you will find the highest concentrations and where to screen your monitoring well accordingly.
What is the difference between correlation and causation. Give an example.
Correlation is when two variables have a statistical relationship but it may not necessarily be connected or dependent. Correlation does not imply causation so in statistics it is important to understand and examine the two. Causation is when two variables are related where one directly affects the other. An example to compare the two would be that ice cream sales increase as sunglass sales increase. These two are not actually related, they just appear to be since they both trend the same. However, ice cream sales and outside temperature are correlated- the hotter it gets the more likely you are to go buy ice cream. Sunglass sales and ice cream appear related since they both trend in similar ways, but the reality is they both are related to weather rather than to eachother at all.
needs and Tyler will reply soon.