Find the probability that a non leap year is not a sunday

Are the roots of ax 2 + bx + c = 0 reciprocal of each other?

The volume of a box of detergent is slightly less than one fifth of a liter. what is the maximum number of laundry loads that can bewashed if each load requires a minimum of 3/4 ounces of detergent, assuming a liter contains 100 ounces? ​

The harmonic mean for the numbers 2, 3, 5 is (i) 2.00 (ii) 3.33 (iii) 2.90