20000*0.45 = 9000 in the bond
20000*0.15 = 3000 in the CD
20000*0.20 = 4000 in stocks
20000*0.029 = 580 in savings
A=9000(1 + 4.35%)^3 = 10,226.33
A=3000(1 + 2.90%)^3 = 3,268.64
A=4000 (1 + 8%) x (1 - 4%) x (1 + 6%) = 4,396.03
A=580(1 + 4.35%)^3 = 4,545.04
Total value = 22,436.04
Gain = 22,436.04 - 20,000 = 2,436.04
8+.90+.07
This the answer because you have to make it as an addition way.
Hope I helped.
