The answers are highlighted in yellow but can someone explain the steps and formulas used to get to those answers? thanks

The following standard overhead costs were developed for one of the products of Raptor Company: The following actual information is available regarding the company's operations for the peric \begin{tabular}{|l|c|} \hline Units produced & 20,000 \\ \hline Direct labor & 115,000 hours \\ \hline Overhead incurred: & \\ \hline Variable & $437,500 \\ \hline Fixed & $1,320,000 \\ \hline & $1,757,500 \\ \hline \end{tabular} Budgeted fixed overhead for the period is $1,350,000, and the standard fixed overhead rate is based on expected capacity of 90,000 direct labor hours. Required: Correct Answer 1) Calculate the variable overhead spending variance. 22500 2) Calculate the variable overhead efficiency variance. 60000 3) Calculate the fixed overhead spending variance. 30000 4) Calculate the fixed overhead volume variance. 150000