Task 1

Please create two data frames according to the following two tables

Table 1->classroom_capacity

Classroom_id	Capacity
1	23
2	25
4	20

Table 2-> classroom_size

Classroom_id	size
1	900
2	800
3	850

Task 2

Please do an inner join for these two tables. Call the result data frame df1.

Task 3

Please do an outter join for these two tables, while keeping all the classroom_id in the classroom_capacitytable. Call the result data frame df2.

Task 4

Extract the capacity column from the classroom_capacitydata frame and call it mydata, then calculate the mean capacity using R programming

Task 5

Please define a data frame as the following. df=data.frame(

name=letters[1:5],

age=c(9,130,-2,3,15)

)

Now for invalid age input (either greater than 100 or smaller than 0), please replace them with a text string invalid.

Hint: you will need logical subscripting for the data frame.

use R