Answer: a) Temperature of 
b) 
c) dehydrating agent
Explanation:
Ethanol is heated with an excess of concentrated sulfuric acid at a temperature of 170°C to produce ethene.
The balanced chemical reaction is:

Here concentrated sulfuric acid removes a water molecule from ethanol and thus acts as a dehydrating agent.
Answer:
Forest Fire
Explanation:
Forest fire is an ecological factor over which biological processes like seed dispersal and their germination is dependent upon. Some plants germinate under high temperature underground regions of the soil which is covered by the hot soil affected by the burning by the forest fire. Some of the coniferous trees like longpole pines have hard cone which exhibit the seeds. These cones exhibit the serotonin resins which are melted by the forests fire hence fire helps in dispersal of the seeds. Other plants like Eucalyptus and Banksia are also dependent upon fire for seed dispersal.
What do you mean tell me one thing you learned what did you learn
Erosion, ocean waves and weathering.
Answer:
70000 cm in 7km
Explanation:
There are 1000 m and 100 cm in 1 m in 1 km, so to find how many cm are in 7 km you need to do 10000 x 7. You get 70000
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