The earliest introduction of zebra mussels in united states probably occurs in 1986.
At that time, commercial vessels from Europe went to north America as a place for freshwater ballast stowaway. They merchants then introduced zebra mussels to the market and it gained popularity ever since. They also introduced zebra mussels population in local lakes and let them reproduce there.
Natural minerals would be the best answer. people travel to Russia for the literature and art as well as its forests and beaches.
The countries are France, Central Europe,Italy, Belgium, Netherlands,Spain,west Indies
Answer:
In "smoke-filled room" studies, smoke billowed from a vent in a room. If the research participant in the room was alone, he or she was more likely to get help quickly. If the participant was with a crowd, he or she was likely to either take much longer to get help or not get help at all.
Explanation:
This experiment was conducted by John Darley and Bibb Latané during the 1960s, Columbia University, participants were told to fill questionaries while in a room if the participant was alone in all of the cases they run to the hall to tell someone about the smoke, but in the other part of the experiment the participant was in a room with other people which were confederates of the researchers, and were told to say or do nothing about the smoke, and to say they did not know if they were asked about it, in this part of this experiment 9 of 10 participants stayed quiet and finished the test watching the smoke but refusing to move because of the social pressure.