7) Un cuerpo realiza un movimiento M. A.S sujeto al extremo de un resorte (ver figura). Diga si el tiempo que tarda en efectuar una vibración completa aumentará, disminuirá o no se alterará,

en cada uno de los siguientes casos (explique brevemente):

a) El cuerpo es sustituido por otro de menor masa.

b) El resorte es sustituido por otro más duro.

SUGERENCIA: Analice la fórmula del periodo √

donde m es la masa del cuerpo y k es la

constante de elasticidad del resorte.​

Which supports the idea that birds and butterflies both have wings but they do not have a common ancestor with wings? a. the wings are analogous structures that evolved differently and do not have a similar internal structure. b. the wings are homologous structures that evolved differently and do not have a similar internal structure. c. wings of birds are vestigial structures, but the wing structures of bats are not vestigial. d. wings of bats are vestigial structures, but the wing structures of birds are not vestigial

The following reaction shows sodium carbonate reacting with calcium hydroxide. na2co3 + ca(oh)2 → naoh + caco3 how many grams of naoh are produced from 20.0 grams of na2co3? (molar mass of na = 22.989 g/mol, c = 12.01 g/mol, o = 15.999 g/mol, ca = 40.078 g/mol, h = 1.008 g/mol) 12.2 grams 15.1 grams 24.4 grams 30.2 grams

Water's surface tension and heat storage capacity are accounted for by its a) orbitals b) weight c) hydrogen bonds d) mass e) size