Can someone please help with the subset function in R

[AlphaOShadow23]

Can someone please help me with this, I am new to R and I am so confused. I have to create a subset but can't seem to get it right. Please can anyone help and let me know what to input? Thanks.[The red bit is where I am stuck at]

[andresrcs]

It seems you have skipped the part of the code where you load the data, you can't subset something that doesn't exist so look for the instructions to load the required data set.

If you need more specific help, please provide a proper REPRoducible EXample (reprex) illustrating your issue.

[EconProf]

Your code subsets an existing dataset called pb_only and assigns the result as pb_only. Does pb_only already exist? If not, what is the name of the dataset you are working with in this exercise? Use that data in the subset() function.

[technocrat]

Using the built-in mtcars illustrates two solutions

subset(mtcars, carb == 4)
#>                      mpg cyl  disp  hp drat    wt  qsec vs am gear carb
#> Mazda RX4           21.0   6 160.0 110 3.90 2.620 16.46  0  1    4    4
#> Mazda RX4 Wag       21.0   6 160.0 110 3.90 2.875 17.02  0  1    4    4
#> Duster 360          14.3   8 360.0 245 3.21 3.570 15.84  0  0    3    4
#> Merc 280            19.2   6 167.6 123 3.92 3.440 18.30  1  0    4    4
#> Merc 280C           17.8   6 167.6 123 3.92 3.440 18.90  1  0    4    4
#> Cadillac Fleetwood  10.4   8 472.0 205 2.93 5.250 17.98  0  0    3    4
#> Lincoln Continental 10.4   8 460.0 215 3.00 5.424 17.82  0  0    3    4
#> Chrysler Imperial   14.7   8 440.0 230 3.23 5.345 17.42  0  0    3    4
#> Camaro Z28          13.3   8 350.0 245 3.73 3.840 15.41  0  0    3    4
#> Ford Pantera L      15.8   8 351.0 264 4.22 3.170 14.50  0  1    5    4
mtcars[which(mtcars["carb"] == 4),]
#>                      mpg cyl  disp  hp drat    wt  qsec vs am gear carb
#> Mazda RX4           21.0   6 160.0 110 3.90 2.620 16.46  0  1    4    4
#> Mazda RX4 Wag       21.0   6 160.0 110 3.90 2.875 17.02  0  1    4    4
#> Duster 360          14.3   8 360.0 245 3.21 3.570 15.84  0  0    3    4
#> Merc 280            19.2   6 167.6 123 3.92 3.440 18.30  1  0    4    4
#> Merc 280C           17.8   6 167.6 123 3.92 3.440 18.90  1  0    4    4
#> Cadillac Fleetwood  10.4   8 472.0 205 2.93 5.250 17.98  0  0    3    4
#> Lincoln Continental 10.4   8 460.0 215 3.00 5.424 17.82  0  0    3    4
#> Chrysler Imperial   14.7   8 440.0 230 3.23 5.345 17.42  0  0    3    4
#> Camaro Z28          13.3   8 350.0 245 3.73 3.840 15.41  0  0    3    4
#> Ford Pantera L      15.8   8 351.0 264 4.22 3.170 14.50  0  1    5    4