To find out how much Ms. Tanaka will earn for selling 12 televisions, we can use the provided formula:
\[ \text{Total Earnings} = 2,500 + 100t \]
where \( t \) is the number of televisions sold. We need to evaluate this for \( t = 12 \).
Plugging in the value of \( t \):
\[ \text{Total Earnings} = 2,500 + 100(12) \]
Calculating the income from the televisions:
\[ 100(12) = 1,200 \]
Now, adding this to the base salary:
\[ \text{Total Earnings} = 2,500 + 1,200 = 3,700 \]
Therefore, Ms. Tanaka will earn $3,700 for selling 12 televisions this month.