[Q]: Donald Clark "Donny" Osmond (born December 9, 1957) is an American singer, actor, radio personality, and former teen idol. Osmond has also been a talk and game show host, record producer and author. In the mid-1960s, he and four of his elder brothers gained fame as the Osmonds. Osmond went solo in the early 1970s, covering such hits as "Go Away Little Girl" and "Puppy Love". Donny Osmond has always been a solo artist.
[A]: No

[Q]: Gloria Stavers (October 3, 1927 April 1, 1983) was the editor in chief of "16 Magazine". Her personality gave this teen celebrity magazine its stamp for many years. Stavers is credited with being one of the first women rock and roll journalists, but male editors, detractors and those who scoffed at teen or celebrity magazines sometimes called her "Mother Superior of the Inferior". Most people didn't like Gloria Stavers.
[A]: It's impossible to say

[Q]: In theoretical physics, particularly in discussions of , Mach's principle (or Mach's conjecture) is the name given by Einstein to an imprecise hypothesis often credited to the physicist and philosopher Ernst Mach. The idea is that local inertial frames are determined by the large scale distribution of matter, as exemplified by this anecdote: A philosopher has a physics principle named after him.
[A]: Yes

[Q]: Cavalry Sunday is the annual parade of the Combined Cavalry Old Comrades Association which takes place in Hyde Park each year. Retired members of the cavalry regiments march to a service and commemoration around the band stand in the SE corner of Hyde Park and the nearby memorial to the bombing which took place there. The old troopers typically wear bowler hats and march with furled umbrellas. It rained in Cavalry Sunday this year
[A]:
It's impossible to say