The equations would be
Value: b + c = 19000
Interest: 0.07b + 0.09c = 1590
0.07b + 0.09 (19,000 - b) = 1,590
0.07b + 1,710 - .09b = 1,590
120 = .02b
B = 6,000
C = 13,000
So the correct answer is d. $6000 in bonds; $13,000 in certificates of deposit.
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