David James is a cost accountant and business analyst for Doorknob Design Company $($DDC$),$ which manufactures expensive brass doorknobs. DDC uses two direct cost categories: direct materials and direct manufacturing labor. James feels that manufacturing overhead is most closely related to material usage. Therefore, DDC allocates manufacturing overhead to production based upon pounds of materials used.

At the beginning of $2009,$ DDC budgeted production of $100,000$ doorknobs and adopted the following standards for each doorknob:

Input Cost$/$Doorknob

Direct materials $($brass$)0\mathrm{.}5$ lbs @ $$20/$lb $$10\mathrm{.}00$

Direct manufacturing labor $0\mathrm{.}25$ hours @ $$30/$hr $$7\mathrm{.}50$

Manufacturing overhead:

Variable $$10/$lb x $0\mathrm{.}5$ lbs $$5\mathrm{.}00$

Fixed $$5/$lb x $0\mathrm{.}5$ lbs $$2\mathrm{.}50$

Standard cost per doorknob $$25\mathrm{.}00$

Actual results for April $2009$ were:

Production $95,000$ doorknobs

Direct materials purchased $50,000$ lbs @ $$22/$lb

Direct materials used $45,000$ lbs

Direct manufacturing labor $20,000$ hours for $$650,000$

Variable manufacturing overhead $$400,000$

Fixed manufacturing overhead $$350,000$

$1$

For the month of April, compute the following variances, indicating whether each is favorable $($F$)$ or unfavorable $($U$)$

a Direct materials price variance $($based on purchases$)$

b Direct materials efficiency variance

c Direct manufacturing labor price variance

d Direct manufacturing labor efficiency variance

e Variable manufacturing overhead spending variance

f Variable manufacturing overhead efficiency variance

g Production$-$volume variance

h Fixed manufacturing overhead spending variance

$2$ Can James use any of the variances to help explain any of the other variances? Give examples.