I do not understand how the annual subsidy benefit is calculated in the financing side effects. The answer given is Annual subsidy benefit $42,970,000 x 60% x 0·025 x 80% = 515·64
I do not understand why 10-year government debt yield rate 2.5% used here, and what 80% means in the calculation.
The 2.5% isn’t the government debt yield rate (that is just a coincidence). It is the difference between the normal borrowing rate of 4% and the subsidised rate of 1.5%. So the subsidy is 4 – 1.5 = 2.5%.