You are thinking of building a new machine that will save you $ 4 comma 000$4,000 in the first year. The machine will then begin to wear out so that the savings decline at a rate of 1 %1% per year forever. What is the present value of the savings if the interest rate is 9 %9% per year?

The present value of the savings=$37,064.22

Explanation:

The present value of the savings is the amount that it worths today, this  would be done in two stages;

The first stage is to determined the present of the first cash savings as follows:

PV of the first payment = 4,000 × (1.09)^(-1)=3,669.72

Second step is to determine the present value of the declining perpetuity

PV of declining perpetuity. A perpetuity is the series of cash flow occurring for  the foreseeable future of years.

A- 4,000, g-negative growth rate = 1%,  

interest rate = 9%

PV in year 1 = 4,000× (1-0.09)/(0.09+0.01)

   = 36,400

PV in year 0 =   36,400  × (1.09)^(-1) = 33,394.49

The present value of the savings = 33,394.49 + 3,669.72= 37,064.22

The present value of the savings=$37,064.22

answer; enforce the rules;

ans.

heterothermic organisms include those organisms that can switch between homeothermic (having body temperature higher than environment) and poikilothermic (having variation in internal body temperature) strategies.

some migratory birds show heterothermy as they decrease their metabolic rate during cold nights to keep their body temperature low. drop in metabolic rate allows increase in production efficiency of birds that reduces the internal body temperature to make it equal to external cold temperature during cold nights.

thus, the correct answer is 'birds allow their temperature drop in order to increase their production efficiency.'