Blind spots around these large vehicles are called no-zones because occupying these zones is extremely dangerous and not recommended. Truck drivers have serious blind spots into which a car can disappear from view. Also due to the size and weight of their vehicle, truckers must react faster than car drivers.
c. older than
b. the same age as
d. not related to
Limestone is a sedimentary rock composed primarily of skeletal fragments of marine organisms. The presence of fossils reveals the biological origin of these rocks.
A limestone bed containing fossils that are 550 million years old is older than a bed of sandstone containing fossils that are 400 million years old.