Which characteristic of potassium makes it useful for dating rocks?

it has a long half-life.
it decays at an unknown rate.
it produces lead as it breaks down.
it can be used to date all types of rock.

Which of the following best describes the expensive tissue hypothesis? brains require more energy, so the gut had to be reduced, and larger brains and tool use led to higher quality diets. increasing body size means that homo neanderthalensis had to include more fat in its diet. brains require more energy, so the gut had to be reduced as brains got bigger. brains require more fat, so the gastrointestinal viscera (gut) had to expand, and hands were needed to acquire more food.