energy saving from recycling one bottle will power the oven for 7.5 minutes
a glass bottle weighs 500 g
the cost of recycling glass is 5 p per kg
1 glass bottle weighs - 0.5 kg
therefore cost of recycling one glass bottle is -0.5 kg x 5 p per kg = 2.5 p
so to power the oven for 7.5 minutes - 1 glass bottle is used
6 hours is equivalent to 6 x 60 = 360 minutes
therefore to power for 360 minutes - 1/7.5 x 360 = 48 glass bottles are needed
and the cost for 1 glass bottle is - 2.5 p
therefore for 48 glass bottles cost is - 2.5 p/bottle x 48 bottles = 120 p
1 p is 0.01 dollars
so the cost in dollars is - 120 p x 0.01 dollars/p = $ 1.20
answer is $ 1.20
