Compare the luminosities of a `a` magnitude and `b` magnitud…

Compare the luminosities of a `a` magnitude and `b` magnitude stars*.  You will then use your answer to interpret the next question. Please read and comply with my (not optional) input instructions. Hint:  See equation sheet in the exam instructions for guidance. Input Instructions: In typing your answer, only type a number rounded to one decimal place (i.e. 350.475 would be written as 350.5).  Do not include any units, E, words, or scientific notation.  Seriously, just a number. Use standard comma placement if necessary. If your answer does not match my answer exactly, you will not receive credit.  *If any technical issue prevents you from typing into the input box, just write out your answer following the same input instructions in the bonus section at the end of the exam. 

4. The soil that our plant was growing in was low on Fe2+, a…

4. The soil that our plant was growing in was low on Fe2+, and the plant is now iron-deficient, shown below.  It turns out that the soil is low on Fe2+ because it is acidic. Briefly explain why acidic soils are more likely to be nutrient-poor than pH-neutral or alkaline soils. (2-4 sentence limit) Extra credit – 1pt Is this a deficiency in a mobile element or an immobile element? Explain how you can tell. (1-2 sentences)