On January $1,2021,$ Kendall Inc. began construction of an automated cattle feeder system. The system was finished and ready for use on September $30,2022.$ Expenditures on the project were as follows:$$

January $1,2021$

$

$200,000$

$$

September $1,2021$

$300,000$

$$

December $31,2021$

$300,000$

$$

March $31,2022$

$300,000$

$$

September $30,2022$

$200,000$

$$

Kendall borrowed $$750,000$ on a construction loan at $12\%$ interest on January $1,2021.$ This loan was outstanding throughout the construction period. The company had $$4,500,000$ in $9\%$ bonds payable outstanding in $2021$ and $2022.$

The weighted$-$average interest rate in $2021$ under the weighted average method was:

$$

$12\%.$

$$

$9\mathrm{.}43\%.$

$$

$9\%.$

$$

$10\mathrm{.}5\%.$