a) You have a \( \$ 60 \) gift card to a local café and spend \( \$ 3.50 \) of that to buy a pastry every day. \( f(x)= \) b) A sample of 500 bacteria is treated with a medicine that kills half of them every hour. \( f(x)= \) c) A gym has a one-time sign-up fee of \( \$ 90 \) and monthly memberhip dues of \( \$ 20 \). \( f(x)= \) d) A job offers a starting salary of \( \$ 38,000 \) with yearly raises of \( 4 \% \). \( f(x)= \)

For each of your scenarios, we can express them in function notation that captures the situation with respect to \( x \), which we'll define based on the context of each situation. a) If you have a \( \$60 \) gift card and spend \( \$3.50 \) each day, the function can be represented as: \( f(x) = 60 - 3.50x \) where \( x \) is the number of days. b) Starting with 500 bacteria and halving every hour, the function becomes: \( f(x) = 500 \left( \frac{1}{2} \right)^x \) where \( x \) is the number of hours that have passed. c) With a gym's sign-up fee of \( \$90 \) and \( \$20 \) monthly dues, the function can be expressed as: \( f(x) = 90 + 20x \) where \( x \) is the number of months. d) For a job starting with a salary of \( \$38,000 \) plus yearly raises of \( 4\% \), the function is: \( f(x) = 38000 \times (1.04)^x \) where \( x \) is the number of years worked. This is a fun way to visualize how your money or growth changes over time in various real-life scenarios!