Step-by-step explanation:
A compound contains atoms of different elements chemically combined together in a fixed ratio. An element is a pure chemical substance made of same type of atom. ... Compounds contain different elements in a fixed ratio arranged in a defined manner through chemical bonds. They contain only one type of molecule.
12+14+16=42 is your answe
(b) Perpendicular lines have to intersect at angle 90.
Answer:
49π cm²
Step-by-step explanation:



Therefore, the area of a circle of radius 7 is 49π cm²
7,24,25 ~ x,72,75
so x/7 = 72/24 = 75/25 = 3
then x = 7*3 = 21