Mrs. B. invested $30,000; part at 5%, and part at 8%. The total interest on the investment was $2,100. How much did she invest at each rate?  Pick:
A) x = $1,000, y = $29,000
B) x = $5,000, y = $25,000.
C) x = $10,000, y = $20,000.
D) x = $15,000, y = $15,000
E) x = $20,000, y = $10,000
2100 = (30000-x) 5/100 + 8x/100   Solving, we get x = 20000   So, answer is 10000 &amp; 20000   Answer = x = $10,000, y = $20,000.
<result>C</result>
Mrs. B. invested $30,000; part at 5%, and part at 8%. The total interest on the investment was $2,100. How much did she invest at each rate?