Which of these most threatens the waters of the niger river ? A. industrial pollution
B. nuclear pollution
C. overcrowding
D. erosion
pls help me thx

Sammi is studying the interaction of the digestive and circulatory systems in the human body. she has listed various processes that occur in each of the systems. put the processes in order to describe the interaction between these two systems. tiles nutrients diffuse through the villi of the small intestine.digestive processes break nutrients down in the mouth, stomach, and small intestine.blood is pumped through the circulatory system to deliver nutrients to other organs.nutrients are ingested at the mouth.nutrients enter the capillaries of the circulatory system. sequence

Living cells cannot use heat to provide the activation energy for biochemical reactions because which choice(s) complete the sentence correctly? a) answer choice ii. eliminate b) answer choices ii and iv. c) answer choice iii and iv. d) all answers can complete the sentence.

How is the national wildlife refuge system similar to the pacific region coastal program? a. both programs are concerned with providing habitats for wildlife b. both programs are primarily concerned with preserving fish species c. both programs have set aside 150 million acres of land d. both programs are under the u.s. fish and wildlife service