Electricity could be discovered using batteries based on zinc or lead, but without copper wiring it would remain little more than a scientific curiosity. Electric motors and generators require large amount of wiring, so they are impossible to build on large scale in this world
I think either rapid of human population growth or global warming
Answer: Excretory
Explanation: My grandpa went through this recently and I had to learn all about it. :(
Answer:
The waiting room became the conditioned stimulus.
Explanation:
Conditioned stimulus is the reflexive behaviors or the learned behavior.
This stimulus may be defined as a neutral stimulus that with some time and some training will evoke a response by continuously being associated with any other natural occurring stimulus.