Please provide complete solution, thank you Equipment Scheduling

You are to undertake a condominium project with two high$-$rise buildings. Given the constraints that the site only has one excavator and one tower crane, analyze the activities below to give the shortest possible duration of the project.

$\backslash$table$[[$Construction Phase$($s$),$Tower A$,$Tower B$],[\backslash$table$[[$Earthworks$],[($Requires Excavator$)]],5$ months,$6$ months$],[$Foundation Works,$4$ months,$4$ months$],[$Building Superstructure,$8$ months,$10$ months$],[\backslash$table$[[$Pre$-$cast Panel Installation$],[($Requires Tower Crane$)]],9$ months,$5$ months$],[$Architectural Finishes,$5$ months,$8$ months$]]$

Earned Value

As the Project Manager of a low$-$cost housing project by NHA, your objective is to build four $(4)$ houses per month at a cost of PhP $900,000$ each, completing the project in $12$ months. You are now in the beginning of your $8$ th month and was able to build $30-$houses. Moreover, upon evaluating the project's current Cost Performance Index $($CPI$)$ is at $0\mathrm{.}8750.$

a$.$ What is the actual project cost to date?

b$.$ What is the estimated cost at completion using the CPI and SPI of the Project?

c$.$ Project Progress is currently at what percentage?