A cellphone manufacturing system runs two processes A and $B.$ An analysis of the system indicated

that $C{H}_4$ and $CC{l}_4$ are created in the processes according to the amount of time that they are

running:

$kgC{H}_4=2A+1B$

$kgCC{l}_4=0\mathrm{.}005A+(8^{***}{10}^{-5}{)}^{***}{B}^3$

where A and $B$ represent the time in hours that each process is operated. The company wants to

know how their emissions of GHGs are impacted by running the processes for different times. The

$GW{P}_{100}$ values of $C{H}_4$ and $CC{L}_4$ are $28$ and $-2,110,$ respectively.

a$)$ What is the GWP of the system if $A$ is run for $4$ hours and $B$ is run for $4$ hours?

b$)$ Create a "spider plot" $($see slide $5$ of L$17)$ to assess the sensitivity of the GWP of the system to

Processes A and $B.$ The $x$ axis should be expressed as a percentage change in each input $($ A and

$B,$ hours$)$ from $-75\%$ to $+75\%$ assuming a base case of $4$ hours each. The y axis should be GWP

$(kgC{O}_{2}e).$

c$)$ From your spider plot, is GWP more sensitive to Process A or B$?$ What are the GWP values if the

time of process A was increased by $75\%$ while holding B constant at $4$ hours? How about

increasing $B$ by $75\%$ while holding A constant at $4$ hours?

d$)$ Create similar spider plots for Processes A and $B$ with respect to their mass of emissions of $C{H}_4$

and $CC{l}_4$ versus operating time.

e$)$ Interpret your graphs from b$)$ and d$).$ Assuming the company hired you to help them improve

their environmental performance, what would you tell them about the advantages and

disadvantages of increasing or decreasing operation of Processes A and B$?$ Be sure to do a quick

Google search of $C{H}_4$ and $CC{l}_4$ before answering.