Horseradish is at its best in fall and winter. Like so many other root vegetables, however, it stores well and is often available in decent shape well into spring. Jerusalem artichokes/sunchokes are brown nubs, that look a bit like small pieces of fresh ginger.
Using Ms. or Mrs. in a cover letter depends on whether or not you know the marital status of the woman. If you are ever uncertain, it is always safe to use Ms. because it does not make an assumption about her marital status.
You should always include a cover letter when applying for a job unless you are specifically told not to by the employer. We recommend that you write a cover letter (aka letter of intent) after you have drafted and tailored your resume or curriculum vitae (CV) for a particular job description. For academic faculty and teaching positions, see cover letter instructions in Masters, Ph.D.'s and Postdocs section.