Answer:
The yearly accumulation for the current year is 130
Explanation:
Accumulation is defined as
input - output = accumulation
The accumulation rate is accumulation per unit of time (in this case a year)
The accumulation rate will then be the amount of births, plus the amount of immigrants minus the amount of deaths.
ar = 500*0.2 + 55 - 0.05*500
ar = 100 + 55 - 25
ar = 130