At 9: 00 pm bob leaves his home and starts walking to the bus stop at a constant speed of 9.3 feet per second. bob's house is 4320 feet from the bus stop. a. define variables for the quantities that are changing (be specific). b. what does it mean to say bob walks at a constant speed of 9.3 feet per second? c. consider the formula d = 4320 – 9.3t i. what does t represent? ii. what does 9.3t represent? iii. what does d represent?

a. define variables for the quantities that are changing (be specific).
 We define variables:
 t = time in second
 d = distance traveled
 The variables that are changing are t and d.
 As the time increases, the distance decreases.

 b. what does it mean to say bob walks at a constant speed of 9.3 feet per second?
 It means that for every second that passes, Bob walks 9.3 feet.

 c. consider the formula d = 4320 - 9.3t i. what does t represent? ii. what does 9.3t represent? iii. what does d represent? 
 For this case we have:
 t = represents the time in seconds
 9.3t = represents the distance traveled by Bob
 d = represents the distance Bob must travel to get to the bus stop.