Annual salary(2012) = $70,000
Annual inflation = 7%
Therefore, the salary you need to earn in 2020 in order to have the same purchasing power can be calculated below
where
n = 8
r = 7/100 = 0.07
PV = 70, 000
The salary you need to earn in 2020 to have the same purchasing power = $120, 273.03
Answer:
the number of grains in the ball is 274,848
Explanation:
Given that;
diameter = 0.5 mm
so radius r = 0.25 mm
first we determine the volume of the ball using the following equation;
V = 4/3×πr³
we substitute
V = 4/3×π(0.25)³
V = 0.06544 mm³
Now form table 1.1 "Grain sizes" a metal with grain size number of 12 has about 4,200,000 grains/mm³
so;
Number of grains N = 0.06544 × 4,200,000
N = 274,848 grains
Therefore, the number of grains in the ball is 274,848
