Answer:
B) Under a microscope he observed box-like compartments of cork tree bark.
He observed a cork under a microscope.
Explanation:
He observed a cork under a microscope.
Hope that helps
Survival rates of newborns
Average life spans
Death rates
level of and access to medicare
Local diseases with high mortality rates (Malaria,AIDS,Dengue, ETC)
Education levels
Economic levels
Governmental programs or laws (available food) ECT
Temperature/environment conditions
Answer - It is a Great Concern because microbes such as a hydra can consume some of that mercury which then a shrimp can consume that microbes which then transfer into the mouth of a trout which then when humans fish they consume the fish which later we get Mercury poisoning.
Reasoning - There are more concern but these are a few and some reasoning.
I think the answer is D. A good indicator is the resting heart rate. Exercise strengthen your heart and it makes it more efficient. The resting heart rate shows of the heart is pumping blood normally each time it contracts. Having a normal resting heart rate would mean a healthy heart.