Among australia’s vast deserts, the is unique because of its treeless surface and its limestone geology.
a. nullarbor plain
b. great victoria
c. great sandy
d. gibson

The correct answer is A. Among Australia's vast deserts, the Nullarbor Plain is unique because of its treeless surface and its limestone geology.

Explanation:

Nullarbor Plain is a lowland area located in Australia, in the states of South Australia and Western Australia, directly north of the Great Bay of Australia.

It is the world's largest single fragment of eroded limestone with a total area of about 200,000 km² and a length of more than 1,200 km from east to west.

It houses the driest point in Australia, Farina. The annual rainfall is 142 mm.  Very low vegetation occurs in the lowland, so-called scrub consisting of low-foamy shrubs of acacia and eucalyptus, there are sunflowers near the coast. Much of the plain has the status of a National Park and is under protection.

(4,-2)

explanation:

6x+4y=16

-6x-9y=-6

-5y=10

y=-2

x=4