A mutation is a change that occurs in our DNA sequence, either due to mistakes when the DNA is copied or as the result of environmental factors such as UV light and cigarette smoke.
If you were born in 1929 or later, you need to work at least 10 years to become eligible for Social Security. The SSA determines eligibility with a system of credits. Basically, you earn up to four credits for every year worked, and you need a total of 40 credits to qualify for Social Security.
Social Security retirement benefits are based on your working history. In order to qualify, you need 40 credits, and you can earn up to four credits per year. For 2015, you earn one credit for every $1,220 you earn, so you only need $4,880 in earnings to rack up four credits.f you start claiming Social Security benefits at your full retirement age, you will receive 100% of your primary insurance amount each month. You can claim Social Security benefits as early as 62. However, your monthly benefits are reduced by about 6% for each year before your full retirement age.