Which of these may be a matter of serious concern for an ENVIRONMENTALIST?
A. commercial extraction of timber and other forest produce to meet urban demands
B. increase in the population of tigers which is a threat to herbivorous animals
C. involvement of more tribal people in the forest conservation than professionals
D. exploitation of migrated labourers by contractors in a construction site

from the answers choices given, A would be a serious concern for an environmentalist.

Explanation:

modal adverbs are used to modify specific verbs that consist of a linking verb (verb of being) and sometimes another verb. examples of modal verbs include can, could, may, might, must, shall, should, will and would.

modal auxiliary. an auxiliary verb characteristically used with other verbs to express mood, aspect, or tense. in english, the most common modal auxiliaries are can, could, may, might, must, ought, shall, should, will, and would. also called modal .

the answer is

r ≈5.641

plug in the area of 100 yards into the equation

100=

divide each side by pi

≈ 31.8309=

take the square root of each side to find r

=r

r ≈5.641