P(t)=640e-0.043t
i need help

The last option is correct: -4.3%

Step-by-step explanation:

Continuous Exponential Growth or Decay

The exponential e is used when modeling continuous growth or decay that occurs naturally such as populations, bacteria, radioactive decay, etc.

If a quantity grows or decays continuously by a fixed percent, the pattern can be described by the function:

Where P(t) is the value at the time t

k is the continuous growth/decay rate. If positive is for growth if negative is for decay.

The given function is:

It can be seen the value of k is:

k = -0.043

Or, expressed as a percentage:

k = -4.3%

The last option is correct: -4.3%

exactly you go it

step-by-step explanation: