1. 4xy

Variables- x and y

Coefficients - 4xy

Literal - xy

Numerical - 4

Constant - 0

2.5xyz - 10

Variables- x,y, and z

Coefficients - 5xyz

Literal - xyz

Numerical - 5

Constant - -10

3. 3ab+20

Variables- a and b

Coefficients - 3ab

Literal - ab

Numerical - 3

Constant - 20

4. 3a²b2-12

Variables- a and b

Coefficients - 3a²b²

Literal - a²b²

Numerical - 3

Constant - -12

5. 3xy - 7ab+ 8

Variables- x,y,a and b

Coefficients - 3xy , -7ab

Literal - xy, ab

Numerical - 3 and -7

Constant -8

explanation is in the picture

correct me if I'm wrong

hope it helps<33