Standard Penetration Test example $4-2$ page $132$

A $6$ in diameter exploratory boring has been drilled through a fine sand to a depth of $19$ ft $.$ An SPT $N-$value of $23$ was obtained at this depth using a USA safety hammer with a standard sampler. The boring then continued to greater depths, eventually encountering the groundwater table at a depth of $35$ ft $.$ The unit weight of the sand is unknown. Compute $N_{1,60},{}^{\text{'}},$ and $D_r$ at the test location, and use this data to classify the consistency of the sand.