If three 15 uF capacitors are connected in series, the net capacitance is
04.5 UF​

v 154.9= 0.9 length length s little over 154.9cm

layers of the earth affect the waves and these effects are seen on instruiments such as seimometers

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.

i already answered it by 34/s