Hi everyone!
I Need a really big help, I have a problem with a dataset in xlsx that I have to analyze for an exam at university. Below I have pasted the link of the dataset and the R script that I wrote for the exam.
The problem of my dataset is on the columns 6° (drinks).
I have a problem in:

summary info to calculate the mean of the 345 different values of the column "drinks" (the column with the problems)

when I try to write the summary table, the column "drinks" give me NA results for each different information (like 1st quartile, median, 3rd quartile, mean, min, max)

I can't divide my dataset into 2 groups, one that has drinks under 5 and the other one that has drinks more than 5

I can't plot drinks with abline to compare with the graphs of "CMV"

I can't calculate the ttest
I know that there are 9 rows With a 0: I tried to change them into 0.0001 but nothing changed on my Rscript. I also checked that column in format information but nothing of different from the other columns (like "CMV" & co.) I really can't understand why.
I know that probably it's an easy and stupid problem/error but now I can't find the solution about that.
someone can help me?
Thanks everybody and sorry for the trouble
Dataset XLSX: https://mega.nz/#!lFZDjATb
Rscript: https://mega.nz/#!ZRgyWAKS
PS. sorry if i didn't selected the right section