Learning task 1. Write the letter that answers the question
1. The continuous breaking up of rock is called
a. erosion
b. weathering
c. siltation
d. landslide
2. Which agents bring weathering on rocks?
a. rainwater
c. caterpillar
b. leaves
d. clouds
3. What factor/factors act on a rock to change it to soil?
a. temperature
c. plans and animals
b. air and water
d. all of the above
-4. Tiny plants growing on rocks produce acid that make the rock's surface
a. smooth and shiny c. soft and weak
b. hard and brittle
d. all of the above
5. Big plants growing on the surface of a rock develop cracks in the rock because of the
a. force exerted by root c. humus they produce
b. acid they produce d. all of the above​