Una mujer de 60 kg sube un tramo de escalera que une dos niveles separados 3.0 m. ¿Cuánto cambia la energía potencial gravitacional de la mujer?

i believe the answer is a

the only real purpose of sputnik 1 was to beat the us into space. we were getting close to launching a useful satellite, explorer 1 - which launched on january 31, 1958. the ussr had to beat that, so they launched sputnik 1 on october 4, 19

causes

fossil fuels burn

cities become more industrialized

human population grows worldwide