How And When To Harvest. Harvest looseleaf lettuce by 2 methods. The best way is to start picking the outer leaves of each plant when they get to be 2 to 3 inches long. Continue picking this way for 4 to 6 weeks until the plant goes to seed (the flower spike grows up out of the center--also called âbolting.â).
Blinders prevent you from seeing to the side and force you to focus on what's in front of you. A cofactor is the number you get when you remove the column and row of a designated element in a matrix, which is just a numerical grid in the form of a rectangle or a square. The cofactor is always preceded by a positive (+) or negative (-) sign, depending whether the element is in a + or - position.
Covariance is a type of value used in statistics to describe the linear relationship between two variables. The higher the covariance between two variables, the more closely their values follow the same trends over a range of data points (in other words, the less the two variables' curves deviate from each other). In our example, we would find the average of our x values by adding the values in the x column in the table above and dividing by the number of values in the column. 2  Adding 1+3+2+5..., we get a total of 44. 3  Dividing this by 9, the number of x values, we get 44/9 = 4.89 as our x average.