Pls help me on this.​

The pyraminx is a rubik's cube-type toy in the shape of a tetrahedron. the pyraminx shown below has edges 15\,\text{cm}15cm long and vertical height h=12.2\,\text{cm}h=12.2cm. the triangle drawn with dashed lines is a right triangle. what is the distance rr? round your answer to the nearest tenth.

The coverage of a base station of a telecommunication company forms a disk with a radius of (kilometers). let be the distance of a cellphone from a base station. assume that the location of cellphones in use are randomly uniformly distributed within the disk. calculate the mean and variance for the random variable.

Is by a(-4, 2), b(-2, 4), c(1, 3), d(2, 2).of ofto . of d′ if90° to a′b′c′d′ (-2, 2) of c″ if90° to a″b″c″d″ (4, -2) of a′′′ if° to a′′′b′′′c′′′d′′′ (3, -1) of b″ if° to a″b″c″d″ (4, 2)