In lecture, we discussed the decrease in compressive strength per increase in entrained air was between 2 to 5%. For example, look at the mixtures at a w/cm of 0.30. There is a 4.6% increase in air and a 2570 psi decrease in compressive strength at 56 day. That is a total decrease of almost 19% for a 4.6% increase in air content. That is also a 19%/4.6$ = 4.13% decrease in compressive per 1% increase in total air content. Does the decrease in compressive strength for the mixtures cast at a w/cm of 0.30 and 0.42 follow this "rule of thumb"? Remember the last number in the mixture designation is the air content. Explain your