What type of sampling is this:

group the students in a local college by year and then randomly select 15 students from each group.

Jace wrote a sentence as an equation. 56 is 14 more than a number. 14+ = 56 which statement best describes jace's work? jace is not correct. the phrase more than suggests using the symbol > and jace did not use that symbol. jace is not correct. he was correct to use addition, but the equation should be 56+ p = 14 jace is not correct. the first number in the sentence is 56, so the equation should start with 56. jace is correct. the phrase more than suggests addition, so jace showed that 14 plus a variable equals 56. o

The fence around a quadrilateral-shaped pasture is 3a^2+15a+9 long. three sides of the fence have the following lengths: 5a, 10a-2, a^2-7. what is the length of the fourth side of the fence?

The polynomial 10x3 + 35x2 - 4x - 14 is factored by grouping. 10x3 + 35x2 - 4x - 14 5x )-20 what is the common factor that is missing from both sets of parentheses?