Temperature of a city changed by -20 degrees Celsius over a 4-week period. The temperature changed by the same amount each week. Part A write an expression to show the average change in the temperature of the city each week Part Simply the expression and explain, using words, what your answer means.​ thanks for any help

The magnitude, m, of an earthquake is defined to be m=log l/s, where i is the intensity of the earthquake (measured by the amplitude of the seismograph wave) and s is the intensity of a “standard” earthquake, which is barely detectable. what is the magnitude of an earthquake that is 1,000 times more intense than a standard earthquake? use a calculator. round your answer to the nearest tenth.

Oliver had $50 on the day before his birthday. after he recived some money for his birthday , he had $75. write and solve eqaution to find how much money oliver received for his birthday. x+50=75

Lines a and b are perpendicular. if the slope of line a is 3, what is the slope of line b?