50 because you make 20% into a decimal and multiply 250 and .20
Pretty sure it would be C
first most important effect is the erosion and the second most important effect is weathering.
It would be 1/4. because 25 divided by 5 is 5. 100 divided by 5 is 20.
5 can be divide again so it would be 1 and 20 can be divided by 5 so it would be 4. Put them together and it would be 1/4.
The length of side c will be 2 m.
