Answer:
a quantitative observation implies that the subject can be measured by quantity, aka amount or in numbers.
Ex 1: adding one gram of salt to one gram of sugar makes two grams of seasoning. in this example, there are individual quantities (1 gram of each) and total quantity (2 grams). this only changes if the substances have a chemical reaction, such as one of them destroying the other, then the weight would change.
Ex 2: a more simple example is the weight of something. putting the substance on a scale (one specifically for whatever you are measuring, whether it be liquid or solid) is the best way to determine its quantity.
A cohesive force is best described as the attraction between two liquid molecules. Cohesive forces are the inter-molecular forces between similar molecules, which cause a tendency in liquids to resist separation. For example a water drop is composed of water molecules that like to stick together
Potassium should have largest atomic radius.......
'cause on moving to right, attractive force between nucleus and electrons increases and causes shielding effect, due to which atomic radius get smaller