What cell structure is best represented by the image? A.
a non-permeable cell wall
B.
a selectively permeable membrane
C.
a waterproof nuclear envelope
D.
a permeable exoskeleton

Asample of radium-226 will decay 1/4 of its original amount after 3200years. what is the half-life of radium-226?

Un cierto gas tiene un volumen de 800ml a 80°c y 600ml a 80°c y 600mmhg de presión. ¿cual será el volumen del gas a condiciones normales? sí el gas es oxígeno, ¿cuál será su peso? y ¿cuántas moléculas están presentes en el sistema?

Read these sentences from the text. near the equator, the tropics receive the most rain on a consistent basis. as a result, the fresh water falling into the ocean decrease the salinity of the surface water in that region. [. .] . . as the salt content of sea water increases, so does its density. what can you infer about how rain affects the density of surface water near the equator?