The correct answers for which numbers are irrational are:
B: \( \frac{3}{11} = 0.\overline{27} \) - This is a repeating decimal, and hence it is rational, not irrational.
C: \( \frac{2\pi}{4} = 1.570796… \) - This is \( \frac{\pi}{2} \), which is irrational because \( \pi \) is an irrational number and any multiple of an irrational number is also irrational.
E: \( \sqrt{8} = 2.82842712 \) - This is an irrational number. It cannot be expressed as a fraction of two integers.
A: -6.398572639 and F: -\frac{15}{16} = -0.9375 are rational numbers because they can be expressed as fractions (the latter is a terminating decimal).
D: \( \sqrt{16} = 4 \) is also a rational number since it is an integer.
So, the correct selections are:
- C (because it involves π which is irrational)
- E (because \(\sqrt{8}\) is not a perfect square and thus irrational).