Problem III $(20$ Points$)$:

A #$5$ bar $($grade $60)$ is being utilized as tension reinforcement in an under$-$reinforced concrete

beam. The beam is at failure $($concrete is crushing$)$ where the #$5$ bar has a strain $=0\mathrm{.}0018$ and a

stress $=52\mathrm{.}17$ksi

Provide the following information:

a$)$ Is the stress in the bar adequate for an under$-$reinforced failure, why or why not? If not,

what is the minimum additional force $($tension or compression$)$ that would need to be

applied to the bar for the stress to be adequate for an under$-$reinforced failure?

$(10$ Points$)$

b$)$ Label where tension control begins on the graph above.

$(10$ Points$)$