Find brings back empty matrix

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When I use the find command the get back empty matrix: 0-by-1 for B and L,but I get an answer for R. help please thanks

This is my code

clear,clc
load rocket.dat
B= rocket(:,4);
R= rocket(:,2);
L= rocket(:,3);
(find(L<40 & L>60))
(find(B<100 & B>200))
(find(R<115 & R<125))

This is the data in rocket.dat for reference

0000000e+000    1.1600000e+002    4.5000000e+001    1.1000000e+002  
0000000e+000    1.1400000e+002    4.2000000e+001    1.1500000e+002
0000000e+000    1.1800000e+002    4.1000000e+001    1.2000000e+002
0000000e+000    1.2400000e+002    3.8000000e+001    9.5000000e+001
0000000e+000    1.2600000e+002    6.1000000e+001    1.1800000e+002