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PROBLEM No$.3(20$ points$)$

Concrete is strong in compression, but weak in tension. A $24-$in wide $x8-$in thick hollow core concrete slab has three equally spaced $3-$in diameter voids$/$holes located as shown. If the maximum allowable tension stress in concrete is $300$ psi, determine the:

a$)$ largest positive moment that can be applied to the slab

b$)$ largest negative moment that can be applied to the slab

Note: The calculation of section properties has been started in the table. You should use that table to determine the section properties your need to complete the rest of the solution.

$\backslash$table$[[$ITEM$,A,\frac{?}{\text{b}\text{a}\text{r}}(y)($from btm$),\frac{?}{\text{b}\text{a}\text{r}}(y)A,$Io$,d,A{d}^2($write on paper$)$