Question

give all answer pleaseeeeeee

Answer 1

1. a
2.a
3.c
4.d
5.b
6.a
7.c

Answer 2

Hey dear friend,

1. The fuel which has lowest calorific value is Coal which is 25 to 30kj/g
2. Increased Concentration of carbon dioxide causes global warming.
3.The exhaustible source of energy is Petroleum gas.
4.Cooking Gas{LPG) burns without a flame.
5.Parrafin wax is not a product of destructive distillation of coal
6.Sound of Frequency 320Hz is of lowers pitch than the sound frequency of 512Hz
7.The 15hZ sound frequency produce sound which we can't hear.

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