Select the correct answer.

if two half-lives have passed since a scientist collected a 1.00-gram sample of u-235, how much u-235 is left now?

There is 0.25 g of U-235, because when a half-life passes, you need to divide by 2. Since two half-lives have passed, you need to divide by 4.

state the principle of separating two immiscible liquids by separating funnel. describe an activity with diagram to separate a mixture of water and kerosene oil. answer: immiscible layers separate out in layers depending on their densities in separating funne