HELP ASAP, it's timed

Which of the following units is not an official si unit? mole liter kilogram ampere

When the chemicals iron sulfide (fes) and hydrochloric acid (hcl) are combined, bubbles appear from the mixture. 1. does the appearance of bubbles indicate a physical or chemical change? 2. why do the bubbles indicate this change? 3. what property is this?

Which is an example of a highly unstable isotope that is often used in fission reactions?