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When testing the efficiency of an air cooled condenser, the refrigerant condensing temperature should be approximately _____ higher than the entering air temperature.

The state of refrigerant in the suction line should be:

The method of defrost that involves circulating a hot liquid in and around the evaporator is _____ defrosting.

A partially iced over evaporator can be caused by_________.

When evaporator temperature cut-out point is reached in a system with pump-down defrost, the thermostat opens the circuit controlling a pump-down solenoid valve in the liquid line.

In a direct expansion (DX) evaporator system, the refrigerant enters the evaporator as______________.

A low refrigerant charge in an air conditioning system will cause___________.

COMMUNITY TESTLET: Use the following testlet to answer questions 41-45.  RESEARCH QUESTION: Which pre-procedural mouth rinse is more effective in reducing bleeding during NSPT, Chlorhexidine (CHX), hydrogen peroxide, or the placebo, salt water (saline solution). HYPOTHESES: A) There is no difference between CHX and hydrogen peroxide. B) There is a difference between CHX and hydrogen peroxide, patients rinsing with CHX will have the least amount of bleeding.  METHODOLOGY: In a double-blind study, SCC students between the ages of 18-21 were the subjects (ages = 19, 18, 19, 21,20, 19, 20, 19, 20, 20, 19). Each participant was randomly assigned to the CHX, hydrogen peroxide, or placebo group. The study was conducted over 4 weeks, 1 quad evaluated per week using the O’Leary Bleeding Index. Each participant rinsed with 5mL of their assigned mouth rinse 15 min prior to treatment.  RESULTS: A parametric test was used to determine if there was a statistically significant difference between the rinses. The results showed an overall statistically significant reduction in bleeding using CHX (p < 0.03). Additionally, an r-value of - 0.87 demonstrates a measure of correlation between bleeding and use of CHX. 42.    What would be the mode from this list of participant ages?a.    18b.    19c.    20d.    21

 Fin-and-tube evaporators circulating the most common types of refrigerants generally have fins made of _____.

26.    In a distribution of scores that is asymmetrical, the distribution can be skewed due to extreme scores. What causes a positive skew? I.    More scores in the lower rangeII.    More scores in the higher range III.    Skewed right (the “tail” is skewed to the right)IV.    Skewed left (the “tail” is skewed to the left) a.    I & IIIb.    I & IVc.    II & IIId.    II & IV