Two aircraft are flying directly away from each other with equal speed. Each
aircraft emits a sound pulse which is
picked up by the other aircraft. What
speed (km/hr) must each aircraft have in
order that the arriving pulse has a frequency one fifth the emitted frequency?
[ ? ] km/hr
Hint: The speed of sound is 343 m/s.

answer and explanation;

composition refers to both the types of minerals within a rock and the overall chemical makeup of the rock while texture refers to the size and arrangement of the minerals or grains that make up a rock. both composition and texture can be used to classify rocks, such as igneous rocks. texture describes how the rock became solid or crystallized from liquid, melted rock. composition of a rock describes the minerals that make up a particular rock.

I'm not sure what your asking buddy.. but i know that you can weld two peices of steel by pure force and pressure.