In Fig.C the three bearings are at the same elevation.

$($a$)$ When all bearings are on solid supports find the value of $R_2.$

$($b$)$ When the center bearing is $0\mathrm{.}040$ in $.$ lower than the other two find the value

of $R_2.$

$($c$)$ Suppose the center bearing is resting on an elastic support that could be

represented by a spring of constant equal to $30,000l\frac{b}{i}n.$ Find $R_2.$