The oleoresin of trees is obtained by cutting a tapping gash in the bark and removing the resin that collects there. acid treatments can also im- prove collection. in this experiment, four trees (dipterocarpus kerrii) will be tapped seven times each. each of the tappings will be treated with a dif- ferent strength of sulfuric acid (0, 2.5, 5, 10, 15, 25, and 50% strength), and the resin collected from each tapping is the response (in grams, data from bin jantan, bin ahmad, and bin ahmad 1987): problem 13.11 354 complete block designs acid strength (%) tree 0 2.55 10 15 25 50 1 3 108 219 276 197 171 166 2 2100 198 319 202 173 304 31 43 79 182 123 172 194 4 .5 7 33 78 5 4 70 determine the effect of acid treatments on resin output; if acid makes a dif ference, which treatments are best?