Suppose that a and b are rational numbers. which expression is equivalent to a - b? A. a+b
B. -a + b
C. a + (-b)
D. -a + (-b)

please help! due today

Choose the correct slope of the line that passes through the points (1, -3) and (3, -5)

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?

The average daily maximum temperature for laura’s hometown can be modeled by the function f(x)=4.5sin(πx/6)+11.8 , where f(x) is the temperature in °c and x is the month. x = 0 corresponds to january.what is the average daily maximum temperature in may? round to the nearest tenth of a degree if needed.use 3.14 for π .