3. Which group experienced the greatest increase in immigrants between these two time
periods?

Between the 1870 and 1900 the largest number of immigrants continued to come from northern and western Europe including Great Britain, Ireland, and Scandinavia. But "new" immigrants from southern and eastern Europe were becoming one of the most important forces in American life.

which time period is this? or is this story fictional, i'm going to need more info to answer this question

part a. there were 250 teenagers surveyed (100% of tenagers = 250)therefore 1 % = 250/100 = 2.5 76% = 1% x 76 = 2.5 x 76 = 190 teenagers of the 250 surveyed liked burgerspart b: jane surveyed 25% (which is equal to 50 teenagers, i.e. a quarter of the teenagers surveyed is 50) to get 100% we simply get 4 quarters, i.e. multiply 50 by 4 = 200 teenagers were surveyed by jane. part c: it is impossible to give an example where a percentage is greater than 100%, since, by definition , percentage means "per 100".