La junta de dilatación de un par de rieles de tren, o separación, permite que las vías siempre permanezcan rectasyno sufran deformaciones debido al cambio de temperatura. Si la longitud de cada riel es de 5 metros y la temperatura
cambia de 17°C a 32°C, determina la longitud final de cada riel y la separación mínima que debe existir entre ellos,
considera que los rieles son de cobre.​

some attention getter quotes to support your thesis regarding brain work could be the following: :

a. storage capacity of your brain is virtually unlimited.

b. your brain produces sufficient electricity to light-up a small bulb.

c. different brain circuits are involved with reading aloud or silently.

d. your brain by itself does not feel pain.

e. reading allows your brain to download info directly.

f. brains of two musicians performing together can synchronize.

what is this from, i cant tell what language he uses without the piece of literature