Jim cycles from his house to school at a constant rate of 35 feet per second. The distance from his house to school is 3250 feet. a. Which of the following is the most appropriate variable definition in this situation? Select the most correct answer. Let $d$ represent the number of feet Jim has cycled since he left his house. Let $d$ represent the number of feet. Let $d$ represent the number of feet Jim has cycled. Let $d$ represent distance. None of the above. b. Which of the following are Varying quantities? Select all that apply. The distance Jim is from his house as he cycles. The rate at which Jim is cycling. The time it takes Jim to reach the school on his bicycle. The distance Jim is from the school as he cycles. The distance from his house to the school. c. Which of the following are Constant quantities? Select all that apply. The rate at which Jim is cycling. The time it takes Jim to reach the school on his bicycle. The distance Jim is from his house as he cycles. The distance Jim is from the school as he cycles. The distance from his house to the school.

Step 1 ：The question is asking for variable definitions and identification of varying and constant quantities. This is a conceptual question and does not require any calculations or Python code to solve.

Step 2 ：For part a, the most appropriate variable definition would be 'Let $d$ represent the number of feet Jim has cycled since he left his house.' This is because $d$ is representing a specific quantity that is changing as Jim cycles - the distance he has covered since leaving his house.

Step 3 ：For part b, the varying quantities would be 'The distance Jim is from his house as he cycles', 'The time it takes Jim to reach the school on his bicycle', and 'The distance Jim is from the school as he cycles'. These are all quantities that change as Jim cycles from his house to school.

Step 4 ：For part c, the constant quantities would be 'The rate at which Jim is cycling' and 'The distance from his house to the school'. These are quantities that do not change as Jim cycles from his house to school.

Step 5 ：Final Answer: a. Let $d$ represent the number of feet Jim has cycled since he left his house. b. The distance Jim is from his house as he cycles, The time it takes Jim to reach the school on his bicycle, The distance Jim is from the school as he cycles. c. The rate at which Jim is cycling, The distance from his house to the school.