Would you please show calculations for these 3 questions?

Billy Stone, Inc., budgets the following amounts for its Buildings & Grounds and Computer Services Departments in servicing each other and the two manufacturing divisions of Signs and Mailers: Used By Building & Grounds Computer Services Supplied By Signs Mailers 0.60 0.30 0.20 0.55 The actual results for the time period were as follows: Used By Supplied By Building & Grounds Computer Services Signs Mailers Buildings & Grounds Computer Services 0.60 0.35 0.30 0.40 Buildings & Grounds Computer Services 0.15 0.25 0.20 0.10 Actual cost data for each department are: Buildings & Grounds Computer Services Fixed $ 50,000 $100,000 Variable $90,000 $21,000 1. Total fixed costs allocated from Buildings & Grounds to the Signs Department, using the preferred allocation basis, by the direct allocation method are a. $37,500. 2. Total variable costs allocated from Computer Services to Mailers Department, using the preferred allocation basis, by the step-down allocation method (begin with Building & Grounds) are c. $16,000. 3. The equation to determine the total variable costs of Computer Services using the preferred allocation basis, for the reciprocal allocation method is d. CS = $21,000 + 0.10 B&G