Which of the following is a positive statement?

a) A humidity level of 90 percent is too high.
b) It is too hot to run outside when the temperature exceeds 80 degrees.
c) The temperature is 92 degrees today.
d) Summer evenings are nice when it cools off to around 70 degrees.

Acommercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at -35°c by rejecting waste heat to cooling water that enters the condenser at 18°c at a rate of 0.25 kg/s and leaves at 26°c. the refrigerant enters the condenser at 1.2 mpa and 50°c. if the compressor consumes 3.3 kw of power, determine (a) the mass flow rate of the refrigerant, (b) the refrigeration load, (c) the cop, and (d) the minimum power input to the compressor for the same refrigeration load.

Photons with the highest energy have the longest period

Which of the following could represent a single-replacement reaction? a. element + compound = element + compound b. element + element = compound c. compound +compound = compound + compound d. compound = element + element