Potassium-40 has a half-life of 1.3 billion years. As the potassium-40 isotope decays, it becomes argon. If a rock was formed with 12 g of potassium-40, approximately how long would it take for 75% of the potassium-40 to be replaced by argon?

Which material would result in the least amount of energy transfer?

Why are convection currents; why are they hotter and colder parts of earth

You are making cookies that call for 3 tablespoons of molasses, but you are having trouble measuring out the thick, syrupy liquid. What could you do to make it easier to pour amd measure this fluid?

What qualities of metamorphic rocks made them very useful and desirable for building?

The surface temperature on Mercury has been measured to be 239 K. What is this temperature in degrees Celsius

What is the nature of the distance time graph for motion of an object.

Write in powers of 10 notation: 3 trillion; five-thousandths; 730,000,000,000,000; 0.000000000082.

Which of the following best describes the difference between a mixture and a pure substance?

What two things change when an object is travelling at a constant speed

Two people are standing on a 3.12-m-long platform, one at each end. The platform floats parallel to the ground on a cushion of air, like a hovercraft. The two people, the platform and a 3.36-kg ball are all initially at rest. One person throws the 3.