Which choice represents a pair of resonance structures? view available hint(s) which choice represents a pair of resonance structures? a. n⋅⋅≡c−s−h and n⋅⋅≡c−s: − : b. o⋅⋅=n⋅⋅−f: and : n⋅=o⋅⋅⋅−f: c. h−h and : i−i: d. o−s⋅⋅⋅=o⋅⋅: and : o⋅⋅=s⋅⋅⋅−o:

the old alchemists made significant contributions to science even though there starting premises were off a bit. their conclusions after failure would steer them into better directions for investigation. science is no more than close observation and the initial mistakes result in rethinking and retrying experiments.

i believe it is-

d.) gravity pulled particles of dust and gas together to form planets.

a gas, having a molecular weight of 13 kg/kmol and a kinematic viscosity of 0.25 cm2/s, flows through a pipe 0.25 m internal diameter and 5 km long at the rate of 0.4 m3/s and is delivered at atmospheric pressure.