1. The buyer of a certain mechanical toy must choose 2out of 4 optional motions and 4 out of 5 optional accessories. how mnay different combinations of motions are available to the buyer?
2. the rectangular solid is made up of 8 cubes of the same size , each of which has exactly one face painted blue. what is the greates fraction of the total surface area of the solid tht cud be blue?
3.a company has 7 employees, 5 of them are regular and two are not.the five members average salary is x dollars,their std deviation is y dollars,and the two memebers each earn x dollars.
column a :std deviation of all seven members
column b:y dollars