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Question 16 4.55 pts A certain substance has a half-life of 4 minutes. A fresh sample of the substance weighing 90 mg was obtained. After how many minutes will there be 23 mg of the substance remaining? 31.6 minutes 5.5 minutes 1.9 minutes 7.9 minutes Question 15 4.55 pts Sal and Aleah were investing money into two different accounts. They both invested $250 each. Sal invested into an account at an annual interest rate of 3.5% compounded monthly and Aleah invested into an account that had an annual interest rate of 3.7% compounded quarterly. Which statement below best describes the two accounts after 5 years? Sal's account has approximately $10 more after 5 years than Aleah's account. Aleah's account has approximately $100 more after 5 years than Sal's account. Sal's account has approximately $50 more after 5 years than Aleah's account. Aleah's account has approximately $5 more after 5 years than Sal's account