Question: What is the occupation of Mark Rankin and Mark Mothersbaugh?
Context: Muzik for Insomniaks, Volume 1 and Volume 2 is a two-studio album series by Devo's co-founder and lead singer Mark Mothersbaugh.  They were originally released in 1988, the same year as Devo's seventh studio album "Total Devo", on the labels Enigma and Rykodisc.  The albums consisted entirely of instrumentals that were performed in the style of easy listening muzak or new-age music similar to Devo's compilation album "E-Z Listening Disc", released the previous year.  Both of the albums were produced, written, arranged, programmed and performed by Mothersbaugh himself and engineered and mixed by former Devo keyboardist and guitarist Bob Casale.  Mothersbaugh once described the albums as "M. C. Escher meets wallpaper." How to Eat Fried Worms is a 2006 American children's comedy film directed and written by Bob Dolman and produced by Mark Johnson and Philip Steuer with music by Mark Mothersbaugh and Robert Mothersbaugh.  It is loosely based on Thomas Rockwell's 1973 children's book of the same name.  It was also produced by Walden Media, and distributed by New Line Cinema. What to Expect When You're Expecting is a 2012 American romantic comedy film that follows the lives of five interconnected couples in the Atlanta area as they experience the thrills and surprises of having a baby, and realize that no matter what you plan for, life does not always deliver what is expected.  It was distributed by Lionsgate, produced by Mike Medavoy, Arnold Messer and David Thwaites, co-produced by Alcon Entertainment, Phoenix Pictures, What to Expect Productions and Georgia Public, edited by Michael Berenbaum, directed by Kirk Jones from a screenplay by Shauna Cross and Heather Hach with music by Mark Mothersbaugh and based on the pregnancy guide of the same name by Heidi Murkoff. The discography of Devo, an American new wave band formed in 1973, consists of 25 singles and 9 studio albums.  Devo was founded by Gerald Casale, Bob Lewis and Mark Mothersbaugh.  Devo currently consists of brothers Mark Mothersbaugh (synthesizers, lead vocals) and Bob Mothersbaugh (guitar and vocals), Gerald Casale (bass guitar, keyboards, vocals) and Josh Freese (drums).  The band rose to prominence in the US during the new wave era with their single "Whip It".  The band have released nine studio albums, ten extended plays, twelve compilation albums, six live albums, one soundtrack album and twenty five singles. Mark Rankin is a Grammy-winning British record and mixing engineer and music producer, who began his career in 2004 as a house engineer at The Exchange studios.  He is a frequent collaborator of music producer Paul Epworth.  Rankin's credits include critically acclaimed albums by Adele, Queens of the Stone Age, Foster the People, Florence and the Machine and Bloc Party. Jihad Jerry & the Evildoers is the solo project of American musician Gerald Casale, best known as a founding member and "chief strategist" of the influential band Devo.  Jihad Jerry also includes contributions from Mark Mothersbaugh, Bob Mothersbaugh, and his brother Bob Casale.  It also adds drummer Josh Freese, who had previously only worked with them when Devo was on tour. Mark Rankin was lead vocalist with Scottish rock band Gun, who were best known for their cover of "Word Up! ", originally by Cameo.  The single was taken from the album "Swagger", and was released in 1994.  Other singles were "Better Days", "Taking on the World" and "Steal Your Fire". "Through Being Cool" is a song by the American new wave band Devo, written by Mark Mothersbaugh, Gerald Casale, and Bob Mothersbaugh.  It appears on the album "New Traditionalists".  The song was a direct attack on new fans who didn't understand Devo's message.  The song was also featured in the 1981 animated film "Heavy Metal" but was not included on the films soundtrack album. Mark Allen Mothersbaugh ( ; born May 18, 1950) is an American singer, songwriter, composer, multi-instrumentalist, record producer, author and visual artist. General Boy is a character created around 1975 by new wave band Devo.  He is usually seen portrayed by Robert Mothersbaugh, Sr., the father of both Devo's lead singer Mark Mothersbaugh and lead guitarist Bob Mothersbaugh.
Answer: singer