Choose the situation which would best be modeled by an exponential decay function.

A.
A bank account has fallen below a minimum balance and is being charged $1.50 per day in fees.

B.
A machine depreciates (loses value) by $1000 in its first year, by $2000 in its second, $3000 in its third, etc.

C.
A student’s test score decreases by 5 points for each question missed.

D.
An island is being eroded away and loses 10% of its beachfront every year.

D

Step-by-step explanation:

A is an arithmetic sequence in that is adds or subtracts the same amount.

B is also an arithmetic is that it takes the original 1000 and adds another 1000 for each year

C is a geometric sequence because it's losing 5× however many questions missed

D is the answer because it says it loses 10% every year, so it loses 10% of the previous year, not the beginning year.

c is the correct answer

step-by-step explanation:

13

step-by-step explanation:

169-1=168

168-3=165

165-5=160

160-7=153

153-9=144

144-11=133

133-13=120

120-15=105

105-17=88

88-19=69

69-21=48

48-23=25

25-25=0

since it took 13times to completely subtract it hence its square root is 13