Two boats start at the same point and speed away along courses that form a 110° angle. If one boat travels at 23 mph and the other bont travels at 34 mph, how far apart are the boats after 30 min.

i just took the test, the correct answer is .. 31.5 in.

large crystals result from very slow cooling.

evaporation of water: this would produce an evaporite which is a sedimentary rock. like a salt pan in a desert. not possible to have volcanic rocks originate this way.

crystalization in molten earth: slow cooling over time. (hundreds to millions of years)

crystalization at earth's surface: this results in fast cooling. (a few hours to a few months or years)

crystalization from cooling off hot water: that would be a hydrothermal deposit. while associated with volcanics they are not volcanic rocks themselves and usually occur fairly rapidly.

you have to find the same variables -3n - 5n so this would be -3n +(-5n) which equals -9n