Doris Invested Some Money at 7% and Some Money at 8

Multiple Choice

Doris invested some money at 7% and some money at 8%. She invested $4,000 more at 8% than she did at 7%. Her total yearly interest from the two investments was $920. How much did Doris invest at each rate?

A) $100 at 7%, $7,900 at 8%
B) $5,000 at 7%, $8,000 at 8%
C) $4,000 at 7%, $9,000 at 8%
D) $4,000 at 7%, $8,000 at 8%
E) $4,500 at 7%, $7,500 at 8%