yes
No, a regular pentagon cannot have congruent sides but non-congruent angles. By definition, a regular pentagon has all sides of equal length and all interior angles equal. In a regular pentagon, the angles are each 108 degrees, ensuring that both the sides and angles are congruent. If the sides are congruent but the angles are not, it would be classified as an irregular pentagon instead.
An... irregular pentagon?
no
is a regular pentagon if all its angles are congruent and is a general pentagon if they are not.
A regular pentagon
Sometimes. For a regular pentagon, all the sides and interior angles are congruent. However, this isn't the case for some pentagons.
For a figure to be regular, all its sides and angles must all be congruent. So if a pentagon is regular, all of its sides and angles are equal to each other.
A polygon that has congruent sides and congruent angles is called a Regular polygon. If the number of sides is given, you can be more specific. Some examples: 3 congruent sides/angles = equilateral triangle 4 congruent sides/angles = square 5 congruent sides/angles = regular pentagon 6 congruent sides/angles = regular hexagon ...and so on, by adding "regular" in front of the shape's name.
A regular pentagon has 5 congruent sides
If it is a regular pentagon then it will have 5 congruent sides.
No, but a regular pentagon is equilateral. Equilateral means that all sides are congruent (equal in measure); to be regular, all angles also have to be congruent.
No, similar pentagons (or any polygon for that matter) must have corresponding congruent angles and all sides must be proportional to its corresponding sides. For example, if a square with a triangle on it is a pentagon, then a regular pentagon would not be similar to it (because corresponding angles are not congruent).