I have a file and i need to find the reverse complement only of every 2nd line- basically of every even line. How do i go about it?

Here"s what the file looks like

@HWI-ST1023:184:C1V8LACXX:7:1101:1142:2247 2:N:0:TGACCA
GTAGGGGCTGCGCGAACGCAAACCCCCGCTGCCACAAATGATCGTCGGACTGTAGAACTCTGAACGTGTA
+GATCTCGGTGGCCGCCGTATCATTAAAAAAA
+
?1=DBB@DCFFFFIGIIII6DGHHIII6@=AEEDDEEC;@C>@?(;;B;@B?9BCDAA3>(:@@CB+8(9
+>@:@CCBB289(259@B9B8?A:@C@>CC@B
@HWI-ST1023:184:C1V8LACXX:7:1101:1450:2022 2:N:0:TGACCA
ACGTGCCCTCGGCCAGAAGGCTTGGGGCGCAACTTGCGTTCAAAGACTCGATGGTTCACGGGATTCTGCA
+ATTCACACCAAGTATCGCATTTCGCTACGTT
+
?@@DDDFFADFFHIJIIFG>FHIJJJJJGIIBH=DHGHHDDFFF;AEAC?=>CD-:@CDBDBDBDD>CDD
+D:ACDCDDDDD?(4>CBBD?@DDDDDDDD8?
@HWI-ST1023:184:C1V8LACXX:7:1101:1457:2047 2:N:0:TGACCA
GCGTCGCCAGCACAGAGGCCATGCGATCCGTCGAGTTATCATGAATCATCAGAGCAACGGGCAGAGCCCG
+CGTCGACCTTTTATCTAATAAATGCGTCCCT
+
@CCDFFFFGHHHHJIIIJJIJJJJIIJJJJFHIBFBFHIGJJIGI@GHGGEHHHHHHFFDDABDDDDDDD
+DDDDBDBBBDCCCCCDDDDCDDEECB8<@DD
@HWI-ST1023:184:C1V8LACXX:7:1101:1476:2196 2:N:0:TGACCA
GATTGGGGCTGCATTCCCAAACAACCCGACTCGTAGACAGCGCCTCGTGGTGCGACAGGGTCCGGGCACG
+ACGGGGCTCTCACCCTCTCTGGCGCCCCTTT
+
C@CFFFFFHHHHHJJJJJJJJJJJJJJJIJJJJGHIIGEGGIJJIIICHH?@DDCDDBDD9CDBBDDDDD
+BDDDDDDDDDCDDDD?BCDCCCDD@BDDDDD

[download]

Thanks in advance guys

EDIT

I'm facing specific problems in performing the reverse complement only on every other lines.

Actually I need to find reverse complement of every second line and JUST THE REVERSE of the fourth line

In reply to find reverse complement of every 2nd line by bingalee

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