Please show step by step solution for each calculation.

Jane Ltd$.$ is a Canadian$-$controlled private corporation. Its refundable dividend tax on hand $($RDTOH$)$ accounts at December $31,2020$ was $ Nil. For its $2021$ taxation year the following transactions occurred:

a$)$ The corporation received non$-$eligible Canadian taxable dividends of $ $40,000.$

b$)$ The corporation received Canadian interest income of $ $30,000$

c$)$ The company received eligible Canadian taxable dividends of $ $50,000$

d$)$ The company paid taxable non$-$eligible dividends of $ $50,000$

Required: $($show all calculations$)$

$1.$Calculate the balances of the Elan Ltd$.$s eligible and non$-$eligible RDTOH accounts at its year end date of December $31,2021.$

$2.$ Calculate the $2021$ dividend refunds for both RDTOH accounts for Elan Ltd$.$