What would the answer be for the two questions? because i'm very stuck

At school there are 526 students and 263 are girls about how likely is it that a randomly chosen student will be a boy

Sanya noticed that the temperature was falling at a steady rate of 1.4 degrees every hour from the time that she first checked her outdoor thermometer. by 6 a. m., the temperature had fallen 21 degrees. which expression can you use to find how many hours earlier she had first checked the thermometer?

Cody was 165cm tall on the first day of school this year, which was 10% taller than he was on the first day of school last year.