Write the Word or Phrase That Best Completes Each Statement $\mathrm { y } = 3 \mathrm { e }^{ .04 x }$

Write the word or phrase that best completes each statement or answers the question.
-A population is increasing according to the exponential function defined by $\mathrm { y } = 3 \mathrm { e }^{ .04 x }$ , where $\mathrm { y }$ is in millions and $\mathrm { x }$ is the number of years. Which of the following should be done in order to answer the question "When will the population reach 4 million?"

A) Evaluate $\mathrm { y } = 3 \mathrm { e }^{ \cdot 04}( 4 )$ .
B) Solve $3 \mathrm { e }^{ \cdot 04 }\mathrm { x } = 4$ .
C) Solve $3 \mathrm { e } ^{\cdot 04 }\mathrm { x } = 12$ .
D) Evaluate $\mathrm { y } = 3 \mathrm { e }^{ \cdot 04} ( 1 / 4 )$ .