Retesting is possible depending on a variety of circumstances. It is possible to retake the ASVAB or PiCAT, but you will need to coordinate this with your recruiting office. In general you may be required to wait a month or more to retake the test; each branch of the service may have different requirements that must be fulfilled in order to retest.
As to the original studio album ("Armed Forces", the supposedly main disc), it's great, though not up to "This Year's Model" which is easily my favorite EC album. The lyrics on the album are especially great. One problem I have though is that the sound quality should be better. I don't know what the problem is, if the source tape is somewhat degraded or if the remastering has been over or under done. It's not terrible, just seems like it should be substantially better fidelity for a recording of a successful (by then) artist at that point in time. That's why I'm knocking off one star, otherwise it would get five stars from me. But the Hollywood High part alone would get five stars, so you might think of this as a great live album plus bonus studio tracks.
As of 2017, the U.S. spends about US$610 billion annually to fund its military forces and Overseas Contingency Operations. Put together, the U.S. constitutes roughly 40 percent of the world's military expenditures. The U.S. Armed Forces has significant capabilities in both defense and power projection due to its large budget, resulting in advanced and powerful technologies which enables a widespread deployment of the force around the world, including around 800 military bases outside the United States. The U.S. Air Force is the world's largest air force, the U.S. Navy is the world's largest navy by tonnage, and the U.S. Navy and the U.S. Marine Corps combined are the world's second largest air arm. In terms of size, the U.S. Coast Guard is the world's 12th largest naval force. 
The Armed Services Vocational Aptitude Battery (ASVAB) is a test that covers basic knowledge such as math and verbal skills, writing skills, and vocabulary. It is a required test for entrance into the military, but it can also be an indicator for general aptitude skills for other purposes. For those looking to go into military service, the ASVAB score is a crucial indicator of prospective job placement, so it is very important to take this test seriously and to focus on your strengths when taking the exam. Higher test scores often mean better jobs, higher salary, and more opportunities for advancement in the military.
One ASVAB sub-measure, the Armed Forces Qualification Test (AFQT)--which is just a separate analysis of the same tests that focuses only on four of the subtests--is also population-referenced, but its score from 1-99 is a percentile score. This means that if you score a 73, you scored as well as or higher than 73% of test-takers in the national sample.