Una clínica realiza un análisis de colesterol en hombres mayores de 50 años, y luego de varios años de investigación, concluye que la distribución de lecturas del colesterol sigue una distribución normal, con media de 210 mg/dl y una desviación estándar de 15 mg/dl. a) ¿Qué porcentaje de esta población tiene lecturas mayores a 250 mg/dl de colesterol?

If a rock is thrown upward on the planet mars with a velocity of 12 m/s, its height (in meters) after t seconds is given by h = 12t − 1.86t2. (a) find the velocity of the rock after two seconds. m/s (b) find the velocity of the rock when t = a. 12−3.72a m/s (c) when will the rock hit the surface? (round your answer to one decimal place.) t = s (d) with what velocity will the rock hit the surface? m/s

Explain why electric current cannot exist if a current doesn't have a voltage source.

The atoms in a nickel crystal vibrate as harmonic oscillators with an angular frequency of 2.3 × 1013 rad/s. the mass of a nickel atom is 9.75 × 10-26 kg. what is the difference in energy between adjacent vibrational energy levels of nickel? (h = 6.626 × 10-34 j • s, , 1 ev = 1.60 × 10-19 j)