Please show work.

Karlson Software Company is located in State H, which enables employers to reduce their contribution rates under the experience-rating system. From 2007 to 2016 , inclusive, the company's total contributions to state unemployment compensation amounted to $14,600. For the calendar years 2017 to 2020, inclusive, the contribution rate for Karlson was 2.7\%. The contributions of each employer are credited to an account maintained by the State Unemployment Compensation Commission. This account is credited with contrbutions paid into the account by the employer and is charged with unemployment benefits that are paid from the account. Starting January 1, 2021, the contributions rate for all employers in State H will be based on the following tax rate schedule: The annual payroll for calculation purposes is the total wages payable durng a 12-month penod ending with the last day of the third quarter of any. calendar year. The average annual payroil is the average of the last three annual payrolls, The SuTA tax rate for the year is computed using the information available (benefits received and taxes paid) as of September 30 of the preceding year. The schedule below shows the total payroll and the taxable payroll for the calendar years 2017 to 2020. Farst Quarte Second Qua Third Quarts Fourth Quar Unemployment benefits became payable to the company's qualified unemployed workers on January 1 , 2007. Between that time and September 30 2020 , total benefits amounting to $14,822.20 were charged against the employer's account. Compute: In your computations, round amounts to the nearest cent. Round your final percentage answers to one decimal place. a. Contribution rate for 2021 , \% b. Rate for 2021 if $1,840 additional benefits had been charged by mistake to the account of Karlson Software Company by the State Unemployment Compensation