Laboratory specific gravity and absorption tests are run on two coarse aggregate sizes, which have to blended.

The results are as follows:

Aggregate A: Bulk specific gravity 2.491; absorption 0.8%
Aggregate B: Bulk specific gravity 2.773. absorption 4.6%

a. What is the specific gravity of a mixture of 50% aggregate A and 50% aggregate B by weight?

b. What is the absorption of the mixture?

c. What should be the proportion of aggregate A in the blend, so that the mixture will have a bulk specific gravity of 2.650?

d. What should be the proportion of aggregate A in the blend, so that the mixture will have an absorption capacity of 4%?