What if the frequency is now increased to f = 87 Hz, and we want to keep the impedance unchanged? (A) What new resistance should we use to achieve this goal? R = Ω (B) What is the phase angle (in degrees) between the current and the voltage now? ϕ = ° (C) Find the maximum voltages across each element.

What color would an object that reflects green and blue light appear to be in white light? a. blue b. cyan c. magenta d. black

A175 g lump of molten lead at its melting point (327 c) is placed into 55.0 g of water at 20.0 c. the specific heat of lead is 130.j/kg c and the hf of lead is 20,400 j/kg. when the lead and the water have reached equilibrium, what is the temperature of the mixture?

30 points - when can a theory be modified if a new type of technology allows for new observations that raise new questions? a. immediately, while the questions about the theory are being asked b. after new hypotheses related to the theory are tested in experiments c. only after the new observations disprove all parts of the theory d. while scientists begin to think about how the theory could improve