Question

the lockport dolostone forms the cap rock of niagara falls as well as a bluff, or ridge, known as the niagara escarpment. (see figure 15-7.) the falls began where the river reached the crest of the escarpment about 15,000 years ago. erosion is causing niagara falls to move steadily upstream at the remarkable rate of about 2 meters per year.
the adirondack mountains are the only true mountain landscape of new york state. they are an extension of the grenville province, a part of the ancient precambrian core of north america known as the canadian shield. the adirondacks are a great dome, pushed up in the middle to expose a core of ancient plutonic and metamorphic rocks. new yorks highest point, mount marcy, at 1629 meters (5344 feet) is located in the eastern adirondacks.
figure 15-8: the adirondack mountains were pushed up and overlying sedimentary rocks have been eroded away. the figure shows a map with adirondack mountains, tug hill plateau, lake ontario, lake champlain, st. lawrence river, and different rock types: sedimentary rocks, mostly metamorphic rocks, igneous intrusion, mostly metamorphic rocks
the tug hill plateau is located west of the adirondacks. this is a hilly region of poor soils, slow drainage, and abundant snowfall. as a result, the tug hill plateau is one of the most sparsely settled landscapes of new york state.
north of the adirondacks is the st. lawrence river lowlands. this plains landscape follows the st. lawrence river and curves south to the shore of lake champlain.

1. why are the adirondack mountains higher than the surrounding landscapes?

Explanation:

The text states the Adirondacks are a great dome pushed up in the middle, exposing ancient rocks, which makes them higher than surrounding landscapes.

Answer:

The Adirondack Mountains are a great dome that was pushed up, making them higher than the surrounding landscapes.