Quien me ayuda con esta Actividad si no la hago podre graduarme y buej no entiendo mucho las matematicas.. Teoria Combinaria-Permutaciones:

si disponen de 6 libros de matematicas 4 de fisica, y 5 de biologia, si cada uno es de un autor diferente, ¿calcular de cuantas maneras pueden colocarse todos ellos en un estante con la condicion de que los de cada materia esten juntos

Someone answer asap for ! max recorded the heights of 500 male humans. he found that the heights were normally distributed around a mean of 177 centimeters. which statements about max’s data must be true? a. the median of max’s data is 250 b. more than half of the data points max recorded were 177 centimeters. c. a data point chosen at random is as likely to be above the mean as it is to be below the mean. d. every height within three standard deviations of the mean is equally likely to be chosen if a data point is selected at random.