Most of the scots irish who came to the colonies were farm laborers or tenant farmers who were leaving behind droughts and crop failures
Responding to xenophobic concerns, Congress passed an emergency law restricting immigration in 1921. Among other provisions, the Act established a quota (a proportional share of a total) for nationalities on the basis of their numbers in the U.S. in 1910.
The missing detail is: a quota.
Definition -:
Photosynthesis is the process in which green plants use sunlight to make their own food. Plants, algae, and a group of bacteria called cyanobacteria are the only organisms capable of performing photosynthesis
Formula -:
6CO2 + 6H2O → C6H12O6 + 6O2.
Six carbon dioxide molecules and six water molecules, are converted by light energy captured by chlorophyll (implied by the arrow) into a sugar molecule and six oxygen molecules, the products.