What was the cause of the opium war (1839-1842)?

the chinese government wanted to keep sole control of the opium trade.
the british wanted to stop the east india company from dealing opium.
british merchants wanted to continue the opium trade with china.
opium traders launched a series of raids and attacks against britain.

Which of the following statements is true of cause and effect relationships

What was the underlying cause of the cold war?

What important discovery was made by edmond halley and alexis clairaut, using newton's ideas of mathematics and gravity? they created the scientific method to outline how science should be conducted. they were able to find the orbit of a comet and predict the year of its return. they discovered the three newest planets--uranus, neptune, and pluto. they explained why objects appear to have color.