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B. Solve the following worded problems involving exponential equations. [3 points each] 1. At t = 0, there were initially 960 grams of an isotope. The half-life of an isotope is 30 hours. How much time has passed when only 60 grams of the isotope were left? 2. It is 8 o'clock in the morning when a scientist starts examining 25 samples of germs that triples every 4 hours. What time of the day will he found out that the initial 25 germs had already grown to 675