Answer
$$ 847~mV$$
Work Step by Step
We use the given exponential growth formula:
$V=V_oe^{0.025t}$
Where $V_o$ is the initial amount and $t$ is the time.
We substitute $t=45 \ ms$ and $V_0=275 \ mV$:
$$V=V_oe^{0.025t}=275 e^{0.025\cdot 45}\approx 847~mV$$
