Stratified samples are widely used to study large areas of forest. Based on satellite images, a forest area in the Amazon basin is divided into 14 types. Foresters studied the four most commercially valuable types: alluvial climax forests of quality levels 1, 2, and 3, and mature secondary forests. They divided the area of each type into large parcels, chose parcels of each type at random, and counted tree species in a 20- by 25-meter rectangle randomly placed within each parcel selected. Here is some detail:

Choose the stratified sample of 18 parcels. Use Table B, starting at line 130. Enter the first 15 parcels selected below:

Climax 1: A) _______ , B) _______ , C) _______ , D) _______ , E) _________
Climax 2: F) _______ , G) _______ , H) _______ , I) _______ , J) _______ , K) _______ ,
Climax 3: L) _______ , M) _______ , N) _______ ,
Secondary: O) _______ , P) _______ , Q) _______ , R) _______ .

 

Transcribed Image Text:

Forest type Climax 1 Climax 2 Climax 3 Secondary Total parcels 46 62 32 43 Sample size 5 6 3 4 Forest type Climax 1 Climax 2 Climax 3 Secondary Total parcels 46 62 32 43 Sample size 5 6 3 4