(7) The number of crystals that have formed after t hours is give by Ht) 2 20e0''13'. How long does it take for the number of crystals to triple? (8) Carbon-14 is a radioactive isotope that is present in organic materials, and is commonly used for dating historical artifacts. Carbon-14 has a half life of 5730 years. If a bone fragment is found that contains 25% of its original carbon-l4, how old is the bone? (9) Match each equation with its graph. Explain and justify your answer. x) = 111:1: 9(3) =10sx Mm) = log2 3