How many of the following statements is/are correct? -Two variables are said to be confounded when their effects on the response cannot be separated
-The purpose of an observational study is to avoid confounding and to establish causation
- A specific set of experimental conditions applied to the units is called a treatment.
-Matched pairs design is one of the simple and common type of observational studies.
Select one:
a. 3
b. 0
c. 2
d. 4
e. 1

Tomas is making trail mix using granola and walnuts. he can spend a total of $12 on the ingredients. he buys 3 pounds of granola that costs $2.00 per pound. the walnuts cost $6 per pound. he uses the equation to represent the total cost, where x represents the number of pounds of granola and y represents the number of pounds of walnuts. he solves the equation for y, the number of pounds of walnuts he can buy. answer- b tomas added 6 to both sides of the equation instead of subtracting 6. just took the test

Given ab and cb are tangents of p, and m =10°. what is the measure of abp?

What are two numbers that have a sum of 15