What is the relationship between rock density and the velocity of the seismic waves

Ifound this on google i hope this you “the correct answer is: the czech republic's decision in 2003 to join the european union indicated that the czech republic was willing to forge economic ties with other nations. the european union is a political and economic organism composed by 28 states located mainly in european lands.”

H=   2(area/a+b)h= 2(144/a+b)h= 2(144/18+18)h= 2(144/36)h= 2(4)h=8

Geothermic gradient is the rate of increasing temperature with respect to increasing the depth in the earths interior. away from tech tonic plates boundaries, it is about 25-40 c/km (72-87 degrees f/mi) of depth near the surface in most of the world.

i didn’t understand your question but archipelagos are groups of island hope this