Which frog Ringer's treatment should show the largest force of contraction: normal Ringer's, Ringer’s with moderately high calcium, or Ringer’s with moderately high potassium? Do your results (tables and graphs) match what you expect?

Explanation: Well, moderately high calcium is supposed to have the biggest effect on the force of contraction because calcium influx in the driving force for heart contraction... Therefore, the increasing the amount of calcium will increase the heart rate more dramatically. In the results, high calcium levels have a greater percent change in contractile force so that matches what I expected. However, high potassium levels have a greater change in heart rate and that does not match what I expected..

every society, in order to meet the needs of it's people, has to answer three basic questions:

- what should we produce?

- how should we produce it?

- for whom should we produce it?

this questions must be answered in order to, option b, aid in production decisions.

every country can't produce everything, no matter how rich their land is. it may be a matter of technology, resources or geographical conditions. so, these three questions must be resolved in order to get the most of the production of each land.

hope this !