Answer:
A. costly.
Explanation:
The word marginal means costly in the field of economics. In general, the meaning of marginal is small, tiny and low. Marginal refers to the focus on the cost on the product or profit that is earned from selling of that product. Companies use marginal analysis as a tool in order to help them maximizing their profits so here in the sentence marginal refers to the cost.
Articles of Confederation
I believe
<span>I believe the answer is: In a controlled and unstable environment at slower speeds
Controlled environment refers to exercies places with full safety regulations intact in order to avoid fatal accidents. The 'slower speed'in this context does not necessarily mean always do low level workout, but we need to maintain our workout level only to reach 70& - 80% intensity most of the time in order to prevent injuries that might mess up your workout schedule.
</span>
