Do the tests performed to identify DNA exclude the presence of RNA?

Which real-world scenarios below represent physical and chemical changes? -running a car -exploding fireworks -mixing water and powdered drink mix -combining oil and vinegar to make salad dressing -taking aspirin for a headache -diluting bleach with water-digesting dinner-spreading peanut butter on bread

What element breaks down into yttrium-90?

Which compound contain an iron with a 3+ charge