Chapter 11 - Section 11.1 - Sequences - Exercise Set - Page 639: 39

$48ft$ $ 80ft$ $ 112ft$

$a_{n}= 32n-16$ The distance, the Thermos falls in the first second, $a_{1}= 32(1)-16 = 32-16 = 16 ft$ The distance, the Thermos falls in the second second, $a_{2}= 32(2)-16 = 64-16 = 48 ft$ The distance, the Thermos falls in the third second, $a_{3}= 32(3)-16 = 96-16 = 80 ft$ The distance, the Thermos falls in the fourth second, $a_{4}= 32(4)-16 = 128-16 = 112 ft$