The typical force applied with a condenser during restorative procedures is 3.75 pounds for a 0.5 mm diameter nib, 8.43 pounds for a 0.75 mm diameter, and 15 pounds for a 1 mm diameter nib. The force is applied parallel to the long axis of the instrument shaft.

SOLUTION

Altered respiratory pattern, such as breathing through the mouth rather than the nose, could change the posture of the
head, jaw, and tongue. This in turn could alter the equilibrium of pressures on the jaws and teeth and affect both jaw growth and tooth position. 
In order to breathe through the mouth, it is necessary to lower the mandible and tongue, and extend (tip back) the head. 

If these postural changes were maintained, face height would increase, and posterior teeth would super-erupt;
unless there was unusual vertical growth of the ramus, the mandible would rotate down and back, opening the bite
anteriorly and increasing overjet; and increased pressure from the stretched cheeks might cause a narrower maxillary dental arch.

Acetic acid is a key ingredient in the fixing solution used in radiography. It acts as a stop bath, neutralizing the developer and maintaining the acidic environment necessary for proper fixation. Hydroquinone and elon are developer agents, while sodium bisulfate is not typically part of the fixing process.

1) The upper first premolar usually has two canals: This statement is true. While the presence of two canals in the upper first premolar is not guaranteed, it is quite common to find two canals in this tooth.

2) Root canal instruments are best sterilized by a chemical method: This statement is false. The best method for sterilizing root canal instruments is heat sterilization using an autoclave. Chemical methods can be used for surface disinfection but are not adequate for sterilization.

3) All root canals must be enlarged to at least a size 25 file: This statement is true. Enlarging the root canals to a size 25 or larger is a part of the cleaning and shaping process in root canal therapy to ensure thorough debridement and preparation for filling.

SOLUTION
Simon used the orbital plane (a plane perpendicular to the F-H plane at the margin of the bony orbit directly under the pupil of the eye).

According to Simon, in normal arch relationship, the orbital plane passes through the distal axial aspect of the maxillary canine

Malocclusions described as anteropostenor deviations based on their distance from the orbital plane are as follows:

1. Protraction: The teeth, one or both, dental arches, andYor jaws are too far forward, i.e. placed forward or anterior to the plane as compared to the normal where the plane passes through the distal incline of the canine.

2. Retraction: The teeth, one or both dental arches and/or jaws are too far backward, i.e. placed posterior to the plane than normal