There are 13 brunettes and 7 blondes in a Spanish class. The teacher selects two students to run an errand. How many possible outcomes are there if she selects a brunette followed by a blonde?

91 possible outcomes

Step-by-step explanation:

As the teacher selects a brunette followed by a blonde, we just need to find the number of possibilities of choosing a brunnette and the number of possibilities of choosing a blonde:

number of possibilities of choosing a brunette: 13

number of possibilities of choosing a blonde: 7

Then, the number of possible outcomes is the product of these number of possibilities:

13 * 7 = 91 possible outcomes

introduction, methodology, results, discussion

step-by-step explanation:

an observational study is one which consists of actual observation to record data and then analyse the data.

there are a number of factors that should be analyzed before starting an observational study.

the main four factors are:

i) introduction:   this should be analysed to check whether the purpose of the study is correctly established and the data recorded are appropriate for the study

methodology:   the method of collecting the data, such as whether randomly selected, and whether sample size matches with the population to be studied, whether questions asked are easy to answer by common men, etc.

results: then results such as summary of data with comments should be studied thoroughly

discussion:   the last is the discussion, this can be either by management people or persons who are all interested , etc.