You will increase your chances of landing of position if you know what you applying for exactly. Here is the link to the pdf with the positions:
https://www.gpo.gov/fdsys/pkg/GPO-PLUMBO...K-2012.pdf
https://www.gpo.gov/fdsys/pkg/GPO-PLUMBO...K-2012.pdf
"A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects."
— Robert Heinlein