The vertical strain ∈z due to triaxial load (σz,σr,σt=σr) under the center of plate is _________

\(∈_z=\frac{1}{E}[σ_z-23μ(σ_r)]\)

\(∈_z=\frac{1}{E}[σ_z-μ(σ_r)]\)

\(∈_z=\frac{1}{E}[σ_z-2μ(σ_r)]\)

\(∈_z=\frac{1}{E}[σ_z-23μ(σ_r)]\)

\(∈_z=\frac{1}{E}[σ_z-0.43μ(σ_r)]\)

The vertical strain ∈z due to triaxial load (σz,σr,σt=σr) under

1.	The vertical strain ∈z due to triaxial load (σz,σr,σt=σr) under the center of plate is _________
A.	\(∈_z=\frac{1}{E}[σ_z-μ(σ_r)]\)
B.	\(∈_z=\frac{1}{E}[σ_z-2μ(σ_r)]\)
C.	\(∈_z=\frac{1}{E}[σ_z-23μ(σ_r)]\)
D.	\(∈_z=\frac{1}{E}[σ_z-0.43μ(σ_r)]\)
Answer» C. \(∈_z=\frac{1}{E}[σ_z-23μ(σ_r)]\)