The following figures show the spectral types of four main-sequence stars. rank them based on the time each takes, from longest to shortest, to go from a protostar to a main-sequence star during the formation process.
longest to shortest time:
a. m6
b. g2
c. a5
d. o9

Object a has a length of 3 cm, a width of 2 cm, and a height of 4 cm. object b is dropped into a graduated cylinder. it displaces 19 ml of water. the volume of object a is: a: greater than the volume of object b b: less than the volume of object b c: equal to the volume of object b