When designing an experiment to study tree growth, the following four treatments are used: none, irrigation only, fertilization only, irrigation and fertilization. A row of 10 trees is used in the study and each tree is randomly assigned to one of the four treatments. How many different treatment arrangements are possible

286 different treatment arrangements

Step-by-step explanation:

This is a combination problem.

We want to share 10 trees amongst 4 experimental groups.

13C3 = 286 different treatment arrangements.

percentage - 25%

probability - 0.25

we know,

total amount of students in class = 20

total boys = 10

total girls = 10

no of girls who wear glasses = 10/2 = 5

probability of choosing a girl with glasses is =

number of girls wearing glasses/total number of students in the class = 5/20

thus, percentage of selecting a girl wearing glasses will be

= 5/20 × 100

= 5 × 5

25%

therefore,

probability will be 0.25

happy to

pls mark as brainliest

mgxmgzmgzzzlgxhhhx. dlulhx