One of the giraffes, Bernard, is sick. Last week he weighed 2,490 pounds. This week he weighs 2,312 pounds. If w represents the amount of weight lost, use the bar diagram to write an equation and find the amount of weight Bernard lost. A bar diagram. The top bar contains 2,490 and the bottom bars contain 2,312 and w.

The equation used to solve the equation is
The amount of weight Bernard lost is
.

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.

what is the answer?