What do Optical Centers do?

Which of the following statements is true in regard to limited data sets

When a patient becomes angry or embarrassed that they are being asked for payment, what you do to lessen the negative reaction?

Asubstitute is standing at the halfway line waiting to enter the match at the next stoppage of play the ball has gone over the touchline for throwing and referee allows for the substitution to substitute wants to take the throw-in does the substitute first have to enter the field of play before being allowed to take the throw-in