Identify each event as the result of mechanical weathering or chemical weathering.
mechanical weathering
chemical weathering
the minerals in a marble statue react
with water to form acids and pores in
the structure
a piece of rock crumbles after being
constantly thrashed by strong waves.
industrial runoff forms cracks in a
rocky structure in its path.
the rocks in a region are streaked
orange after being exposed to
repeated rains.

Reason:

When the weathering process occurs due to chemical reaction, then it is considered as chemical weathering.

In the first case, minerals of marble statue are reacting with water to cause weathering. In the second case, due to the acidificaion reaction, the change of the color has happened after exposure to the repeated rains.

Reason:

When the rock is broken into simple pieces without any chemical reaction it is considered as mechanical weathering.

In the first cause, due to the abrasion caused by the strong waves, weathering has happened, in the second case industrial run off may be of varying temperature and thus may cause heating or cooling of the rock and causes weathering.

the answer is b: 1.4 km/hr

the wetland preservation movement began in the u.s. in earnest with the clean water act (cwa) of 1972. although not specifically written to protect wetlands, the cwa is comprised of a series of regulations designed to prevent pollutants from contaminating u.s. waters.