Question 3: (20 points) Three mortar mixes with w/c ratios of 0.48, 0.50, and 0.53 were prepared. Three 2-in mortar cubes were prepared for each mix. The cubes were cured for 7 days and then tested for compressive strength. The test results are shown below: Mix 1: w/c ratio = 0.48 Sample 1, Maximum Load = 20350 lb. Sample 2, Maximum Load = 21080 lb. Sample 3, Maximum Load = 20650 lb. Mix 2: w/c ratio = 0.50 Sample 1, Maximum Load = 18870 lb. Sample 2, Maximum Load = 19320 lb. Sample 3, Maximum Load = 18450 lb. Mix 3: w/c ratio = 0.53 Sample 1, Maximum Load = 17160 lb. Sample 2, Maximum Load = 17610 lb. Sample 3, Maximum Load = 18220 lb. Determine the following: a. The compressive strength of each cube. b. The average compressive strength for each mix. c. Plot the average compressive strength versus w/c ratios for all mixes. d. Comment of the effect of increasing w/c ratio on the compressive strength of the cubes. Question (30 mainta)

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