DRUG CLASS AND MECHANISM: Rosuvastatin is an oral drug for lowering blood cholesterol levels. It belongs to a class of drugs called HMG-CoA reductase inhibitors, more commonly referred to as  statins ..RUG CLASS AND MECHANISM: Rosuvastatin is an oral drug for lowering blood cholesterol levels. It belongs to a class of drugs called HMG-CoA reductase inhibitors, more commonly referred to as  statins ..
Natural numbers are naturally used for counting apples (and other things) so they are sometimes called counting numbers. Even some animals other than humans can count and add, so they must be natural. Minus two apples isn't very natural so negative numbers are not included.
Zero is the only integer (whole number) that is neither positive nor negative. In a sense, zero makes negative numbers possible, as a negative number added to its positive counterpart always equals zero. When zero is added to or subtracted from a number, it leaves the number at its original value. Zero is essential as a position holder in the system known as positional notation. In the number 203, for example, there are two hundreds, zero tens, and three ones. Zero indicates that the value of the tens place is zero.