MATH QUESTION - Help me!

[SykoraG]

My Brain is absolutely done - this seems so simple yet I can't figure it out

Joanna French is currently working a total of 12 hours per day to produce 240 dolls. She
thinks that by changing the paint used for the facial features and fingernails that she can
increase her rate to 360 dolls per day. Total material cost for each doll is approximately
$3.50; she has to invest $20 in the necessary supplies (expendables) per day; energy costs
are assumed to be only $4.00 per day; and she thinks she should be making $10 per hour
for her time. Viewing this from a total (multifactor) productivity perspective,
A.) What is her productivity at present and with the new paint?
B.) How would total (multifactor) productivity change if using the new paint raised
Ms. French’s material costs by $0.50 per doll?
C.) If she uses the new paint, by what amount could Ms. French’s material costs increase without reducing total (multifactor) productivity?

[Gonso]

Well, you know your fixed costs. $20/day in supplies, $4/day in energy, $120 for labor/day. The total is $144 per day.

Her variable costs under the existing scheme are $3.50 per doll over 240 dolls/day = $840/day. Her variable costs under the new paint scheme are $3.50 per doll over 360 dalls/day = $1,260/day. Her total costs equal fixed costs per day plus variable costs per day.

Or are you doing the output/KLEMS bit?

[SykoraG]

I'm following KLEMS. This is an output question.