the slant shear test is widely accepted for evaluating the bond of resinous repair materials to concrete; it utilizes cylinder specimens made of two identical halves bonded at 30 degrees. a recent study on different bonding techniques reported that for 12 specimens prepared using wire-brushing, the sample mean shear strength were 19.2 n/mm2 with a standard deviation of 1.58. for specimens that were prepared with a hand chisel, reported a mean shear strength of 23.13 n/mm2 with a standard deviation of 4.01. does the true shear strength appear to be different for the two methods of surface preparation? state and test the relevant hypothesis using a significant level of alpha