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Acompany made a profit of 75000 over a period of 6 years on an initial investment of 15000 what is the annual roi

Aplane is flying at 32,500 feet. it needs to rise to 36,000 feet in two stages.• in stage 1, it rises 5% of its initial altitude of 32,500 feet.• in stage 2, it rises at a rate of 125 feet per minute. how many minutes does it take for the plane to rise during stage 2?

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.