hi can u please help me with thisQ$1.$ A beam $3mm$ thick is cut into a $10mm$ wide strip

and subjected to three$-$point bending with a span of $20$

$mm.$ Failure occurs due to shearing stresses at a load of

$2400N.$

$($a$)$ Calculate the shear strength.

When the span is increased to $40mm,$ failure occurs by tensile fracture from the surface at a load of $1575$

N$.$

$($b$)$ Calculate the tensile strength.

$($c$)$ Find the span at which the transition from shear to tensile failure takes place.

Recall that the normal and the shear stresses are given, respectively, as follows:

${}_x=-\frac{My}{\text{I}},{}_{xy}=\frac{3}{2}\frac{V}{A}(1-\frac{y^2}{c^2})$

Here $x$ is along the span and $y$ is perpendicular to the axis

about which the bending talkes place. $V$ and $M$ are the internal

shear force and bending moments, respectively; $A$ is the

cross$-$sectional area, I is the moment of inertia $($about which axis?$).$ Do you recall what $c$ is$?$