What are the rectangular coordinates for (4.5, -30o) a. (-2.3, 3.9)

b. (3.9, -2.3)

c. (3.9, 2.3)

d. (2.3,-3.9)

Ricardo ran the 400 meter race 3 times his fastest time was 54.3 seconds his slowest time was 56.1 seconds if his average time was 55.0 seconds what was his time for the third race

Will give brainliest what is the value of x? enter your answer in the box.

An automated water dispenser fills packets with one liter of water on average, with a standard deviation of 5 milliliter. the manual says that after a year of operation the dispenser should be tested to see if it needs recalibration. a year later a number of filled packets are set aside and measured separately. it is found that the average packet now contains about 0.995 liters. does the dispenser need calibration? explain your answer.