Consider the truss shown in Figure $2.$ Two loading cases are applied to the joints: $(1)$ approximately $4$ kg of load applied at joint $"$E$",(2)$ approximately $2$ kg of load applied at joint $"$D$"$ and approximately another $2$ kg load applied at joint $"\backslash ($ F $\backslash )".$

The trusses have six load cells attached to the struts, as depicted in Figure $2$ by the shaded rectangles $1-6.$ The struts are connected through hinges at the joints. Please observe the lab carefully and record data from the loading cells.

$($a$)$ Construct a $2-$D Free Body Diagram $($FBD$)$ for the entire truss in Figure $2$ and calculate the supporting forces at point $"\backslash ($ A $\backslash )"$ and point $"1"$ for these two cases. According to the calculation results of the two cases, discuss the impact of loading location.

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$($b$)$ Using the method of sections, calculate the forces in the struts with the load cells $(1-6)$ attached for these two cases.

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$($c$)$ Tabulate the results of both the calculation and the measurement for the two cases. Provide a short discussion of the experimental laboratory for the truss in Figure $2($half a page maximum$)$ and compare your analytical results at load cells $(1-6)$ with the experimental measurements for the two loading cases.