In Model5: Y = b₀ + b₁Xᵢ + b₂Xᵢ² + ei, find the marginal effect of annual income on the health insurance premium.
If b1 = 0.0019393, a person earns a $50,000 yearly wage and salary, what is the marginal effect of the health insurance premium if they have $10,000 extra income?
a) $19.393
b) $1.9393
c) $3.8786
d) $0.19393