Question

the amount of surface enclosed within the boundaries of plane surface iscalled its mass.​

Answer 1

$\huge{\fcolorbox{green}{blue}{ANSWER}}$

$\huge{\fcolorbox{white}{red}{happy brothers day}}$

The amount of surface enclosed by a closed plane figure is called its Area. It is expressed by the number of times it contains a given unit of measure. It is measured in square units. Hence, the answer is Area

Answer 2

Explanation:

The amount of surface enclosed by a closed plane figure is called its Area. It is expressed by the number of times it contains a given unit of measure. It is measured in square units. Hence, the answer is Area

hope it helps