Prime factor is a factor that is a prime number.
Prime factors of :
8 : 2 × 2 × 2. Also can be written as

12 : 2 × 2 × 3. Also can be written as

20 : 2 × 2 × 5. Also can be written as

30 : 2 × 3 × 5
56 : 2 × 2 × 2 ×7. Also can be written as

70 : 2 × 5 × 7
You can find all of them by using Factor Tree [ as shown in the picture] or Dividing by prime numbers.
In 2018, married filing separately taxpayers only receive a standard deduction of $12,000 compared to the $24,000 offered to those who filed jointly. If you file a separate return from your spouse, you are automatically disqualified from several of the tax deductions and credits mentioned earlier.
I might be missing something here, but the picture doesn't show what number 10 & 11 are asking. sorry :/