What did bohr hypothesize about the atom?

that the atom is a positive, solid sphere with electrons in it.
that the atom is one large solid particle.
that the atom is a nucleus only.
that the atom is a nucleus with electrons orbiting around it.

In order for the bug to fly through the air a force has to push the bug forward. identify this force. how does the bug produce

Abookcase has a mass of 38 kg and the coefficient of friction between it and the floor is 0.82 what is the maximum force of friction between the bookcase and the floor a 372n b 305n c 412n d 449n

Beryl states that insulation with the smallest possible thermal conductivity is best to keep a house warm in winter, but worst for keeping a house cool in summer. sapphire insists the reverse is true: low thermal conductivity is good in the summer, but bad in the winter. which one, if either is correct? a. beryl, because low thermal conductivity results in low heat transfer. b. beryl, because low thermal conductivity results in high heat transfer. d. sapphire, because low thermal conductivity results in high heat transfer. e. neither, because low heat transfer is desirable both in summer and in winter.