The following examples use the Orders table to show how the positive and negative unary operators function. When a positive unary operator is set against a negative value, the returned value is negative (positive_value * negative_value = negative_value). When a negative unary operator is set against a negative value, the returned value is positive (negative_value * negative_value = positive_value). Copy. SELECT (DATEPART(day, Order Date) - DATEPART(day, Shipped Date)) FROM Orders WHERE OrderID = '10248' -- Without a unary operator, the value returned is '-12'.
Inmersion oil does not increase magnification. Inmersion oil is needed at high magnifications. Why? High magnifications come with high numerical appertures (although one can have a low-magnification high-numerical apperture objective). High numerical appertures are required to capture more light and improve resolution.
The magnifying power of the scanning lens is 4X. 2. Low-power objective: Used to view objects in greater details. The magnifying power of the low-power objective lens 10X. 3. High-power objective: If your microscope has three objective lenses, this lens will be the longest. It is used to view an object in even greater details. The magnifying power of the high-power objective lens is 40X. 4. Oil immersion objective (on microscopes with four objective lenses): Usually it has a 100X magnification.