A crystal contains a radioactive isotope that has a half-life of 10,000 years. One-eighth (12.5%) of the parent isotope remains in a sample. How old is the sample?

Suppose a man is heterozygous for heterochromia, an autosomal dominant disorder which causes two different‑colored eyes in an individual, produced 25‑offspring with his normal‑eyed wife. of their children, 15 were heterochromatic and 10 were‑normal. calculate the chi‑square value for this observation.

Sorry guys but as you have a small brain

State one method by which you can recognize a perfect square trinomial.