Calculate the z-score for a lake in the northern part of the state with 5,500 algae spores and a lake in the southern part of the state with a mean of 5,500 algae spores.

Information on the cost of things, quantitative data has to do with numbers, qualitative data uses details such as taste, appearance, what it looks like etc. 

Psychologists often talk of the magical number "7" - so it is generally assumed that we can keep 7 (more or less, so 5-9 is the correct answer) items in our short term memory - we know this as a result of many experiments.

we can increase this by chunking, so for example "7 8 9 5 3" is harder to remember than "78 95 3" - try it yourself!

the answer is a)