Two types of phone operating system are being tested to determine if there is a difference in the proportions of system failures (crashes). Fifteen out of a random sample of 150 phones with OS₁had system failures within the first eight hours of operation. Nine out of another random sample of 150 phones with OS₂had system failures within the first eight hours of operation. OS₂is believed to be more stable (have fewer crashes) than OS₁.State the null and alternative hypotheses.