Most stars are at what point in their life cycles?
a. supergiant
c. main sequence
b. giant
d. white dwarf

Two particles of masses m and 2m are placed on a smooth horizontal table. a string, which joins these two masses, hangs over the edge supporting a pulley, which suspends a particle of mass 3m.the pulley has negligible mass. the two parts of the string on the table are parallel and perpendicular to the edge of the table. the hanging parts of the string are vertical. find the acceleration of the particle of mass 3m.

The two required components for a generator

Suppose a comet has an orbital period of 309.1 years around the sun. what is it’s average distance from the sun?