What is a chemical combination of substances

a) a compound

b) an atom

c) a mixture

d) an element

answer

procedural programming, object-oriented programming

explanation

procedural programming is a type of computer programming language that specifies a series of well structured steps and procedures   within its development period of time. it contains a systematic order of statements, functions and commands to complete a computational task or program. it is centered on creating procedures. while object oriented programming is a programming language that is centered on creating objects rather that actions and data rather than logic.. it has four principles which are inheritance, polymorphism, abstraction and encapsulation

at right angles to each other

the answer is c. the lower legs are levers, and the knees are fulcrums. the ankles hold the loads.