Grey rods can be inserted in the core for most of the cycle to control the radial power distribution in the core, or they may reside out of the core and only inserted and withdrawn to make quick small changes to the power level. The Russians have used Dy in the form of Dysprosium titanate as a control rod material.
A rhetorical question is a device used to persuade or subtly influence the audience. It's a question asked not for the answer, but for the effect. Oftentimes, a rhetorical question is used to emphasize a point or just to get the audience thinking. Sometimes, a rhetorical question is asked with the asker already knowing the answer, such as the weather example.
Dialectic or dialectics (Greek: Î´Î¹Î±Î»ÎµÎºÏÎ¹ÎºÎ®, dialektiká¸), also known as the dialectical method, is a discourse between two or more people holding different points of view about a subject but wishing to establish the truth through reasoned arguments. The term dialectic is not synonymous with the term debate. While in theory debaters are not necessarily emotionally invested in their point of view, in practice debaters frequently display an emotional commitment that may cloud rational judgment.