Select the data in the rows at positions [3, 4, 8] (0-indexed from the top of the DataFrame, not row labels) and columns ['animal', 'age'].

Input

  animal  age  visits priority
a    cat  2.5       1      yes
b    cat  3.0       3      yes
c  snake  0.5       2       no
d    dog  NaN       3      yes
e    dog  5.0       2       no
f    cat  2.0       3       no
g  snake  4.5       1       no
h    cat  NaN       1      yes
i    dog  7.0       2       no
j    dog  3.0       1       no

Output

  animal  age
d    dog  NaN
e    dog  5.0
i    dog  7.0