**PLEASE ANSWER ALL PARTS OF THE PROBLEM, EXCEL CAN BE USED IF NEEDED**

The following stockpiles are available (% passing shown):

Sieve Stockpile A Stockpile B Stockpile C Stockpile D Specification

18 mm 100.0 100 100 100 100

16 mm 92.0 100 100 95.0 95-100

12.5 mm 59.8 100 95.7 80.0 70-85

5.0 mm 5.9 95.8 95.2 45.0 40-50

2.0 mm 2.5 59.5 94.9 35.0 30-38

900 m 2.3 42.0 94.6 35.0 27-33

400 m 2.2 31.2 84.1 35.0 22-28

160 m 1.7 19.3 14.7 20.0 6-10

71 m 1.2 11.5 4.4 15.0 3-6

Cost at the

Plant Site

($/ton) 7.00 10.82 9.51 8.88

a. Combine two or more of the stock gradations to obtain the specified gradation.

b. What is an estimate of the cost per ton for the blended aggregate? (materials only)