Three times the sum of a and b increased by a

answer: c

(2, -4)

goes 7 to the

(9, 4)

easy

i'm assuming that it's c.)   volcanoes built the mountains and earthquakes tore them down.

you estimate that the angle of elevation to the top of the 86th floor (the observatory) is 82 .the total height of the building is another 123 meters above the 86th floor.

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