A fatigue test was conducted in which the mean stress was 70 MPa, and the stress amplitude was 210 MPa.   a. Compute the maximum and minimum stress levels.    b. Compute the stress ratio.   c. Compute...

A fatigue test was conducted in which the mean stress was 70 MPa, and the stress amplitude was 210 MPa.   a. Compute the maximum and minimum stress levels.    b. Compute the stress ratio.   c. Compute the magnitude of the stress range.