SOMEONE HELP Garrett must inspect a bridge that goes over a river. He begins 18 feet above water level to inspect the lighting, descends 32 feet to inspect the base of the bridge underwater, then descends another 4 feet to check on the concrete anchoring the base. Which best represents Garrett’s position with respect to the water level? –54 feet
–30 feet
–18 feet
–10 feet

–18 feet

Step-by-step explanation:

Given: Garrett begins 18 feet above water level to inspect the lighting, descends 32 feet to inspect the base of the bridge underwater, then descends another 4 feet to check on the concrete anchoring the base.

a

step-by-step explanation:

step-by-step explanation:

part a. the differences are decreasing, so we know the sequence is not arithmetic. the ratios are constant (=3/4), so we know the sequence is geometric.

part b. from part a, we know the common ratio is 3/4, so each term is 3/4 of the one before. the initial term is the number of gallons at h=1.

g[h] = (3/4)·g[h-1]

g[1] = 384 . . . . initial value required for a recursive definition

part c. the general formula for a geometric sequence is

a[n] = a[1]·r^(n-1)

we have a[1] = 384, r = 3/4, and the term number given by h. the formula that follows is

g[h] = 384·(3/4)^(h-1)

part d. filling in the value and doing the arithmetic, we have

g[12] = 384·(3/4)^11 ≈ 384·0.042235136 ≈ 16.2183 . . gallons

part e. each gallon is 4 quarts, so

16.2183 gal × 4 qt/gal = 64.8732 qt