Most cellphones depreciate (lose value) as they age. A cellphone that costs $1200 will have a value of $520 at the end of 8 years.
a. What is the rate of change of the cellphone’s value with respect to time?

b. Write a formula for its value, V, when it is t years old (for 0
≤t≤

c. Determine the cellphone’s value after 2.5 years. (2 marks)

d. When is the cellphone’s value $800? (2 marks)

m=-16

step-by-step explanation:

1,407.5 hours

step-by-step explanation:

we first convert all the time to hours and then sum them up.

there are 24 hours in 1 day, in 58 days, there are 24 x 58 = 1,392 hours.

there are 60 minutes in 1 hour, thus, 30 minutes will be equivalent to 30 / 60 = 0.5 hours.

therefore, the number of hours it will take mercury to complete a full rotation is 1,392 + 15 + 0.5 = 1,407.5 hours

d. you cannot tell because there are no values shown.