Initially there were 10 bulbs of 60 Watt power
So total power of all bulbs = 60 * 10 = 600 W
now each bulb used for 4 hours daily
so total energy consumed daily



now we have total power consumed in 1 year

cost of electricity = 10 cents/ kWh
so total cost of energy for one year

Now if all 60 Watt bulbs are replaced by 30 Watt bulbs
So total power of all bulbs = 30 * 10 = 300 W
now each bulb used for 4 hours daily
so total energy consumed daily



now we have total power consumed in 1 year

cost of electricity = 10 cents/ kWh
so total cost of energy for one year

total money saved in 1 year

use the formula
v= u+ at
v is final velocity , u is initial velocity , a is acceleration and t is time
put the values
20 = 0+ a×5
a = 4 m/s²
It is electrical energy into connected energy has in relation to the question
I think the answer would be C