Fluorine
Check out the periodic table. Exact mass number of Fluorine should appear as 18.99...
They come from the atmosphere, since plants use carbon dioxide to produce carbohydrates :)
Yes, pH of the soil affects the colour of flower.
Flowering plants grown in acidic soil (pH<7) bears blue flowers or at has a blueish tint.
Whereas, Flowering plants grown in Neutral (pH=7) and Basic (pH>7) soil bears pink and red flowers.
A plant's flower color is determined by a complex balance between chlorophyll, beta carotene, flavonoids,etc in particular pH of the soil to give out vibrant colors like red, blue, pink, yellow,etc.
Answer:2 the lupine dependent butterflies would disappear.
If the spraying of pesticides will remove all the insects then there will be no insect that will pollinate the lupine flowers. So this will cause removal of lupine species from the environment. And the lupine dependent butterflies will not be able to release their egg on these specific flower and will also disappear from the environment.
The removal of lupine flower from the environment will lead disappearing of these lupine dependent butterflies.
