50- Charity Event Participants There are 16 seniors and 15 juniors in a particular social organization. In how many ways can 4 seniors and 2 juniors be chosen to participate in a charity event? 51- Automobile Selection An automobile dealer has 12 small automobiles, 8 mid-size automobiles, and 6 large automobiles on his lot. How many ways can two of each type of automobile be selected from his inventory? 53-Railroad Accidents A researcher wishes to study railroad accidents. He wishes to select 3 railroads from 10 Class I railroads, 2 railroads from 6 Class Il railroads. and 1 railroad from 5 Class Ill railroads. How many different possibilities are there for his study? 57- Nuclear Power Plants How many different ways can a government researcher select 5 nuclear power plants from 9 nuclear power plants in Pennsylvania? 59- Textbook Selection How many different ways can an instructor select 2 textbooks from a possible 17