Please In 4 years, a reef’s elevation fell from 10 mm above sea level to 2 mm below sea level. The expression (-2-10)•4 gives the change in elevation per year. What was the change in elevation in mm per year? A. 2mm/yr B. -2mm/yr

C. 3mm/yr D. -3mm/yr

Explanation please!

answer: it is 1: 47 pm

solution:

the given function is ,

      =

the three roots of this quadratic function is , 0 ,8 and 10.all the roots are real and rational.

if a quadratic equation is of the form ,

sum of the roots = a + b +c= 0+8+10=18=  

product of roots taken two at a time = a b + b c+ c a = 0+80+0=80 =  

product of roots = a b c = 0=  

there are 11 doors in a hall starting from 0 to 11.the entry in the hall is permitted through gate number 0 and exit is allowed through only gate number 8 and 10.so, three roots(0,8,10) of quadratic function is given by entry and exit route of this hall.

13.46

step-by-step explanation:

16.80 x .20 = 13.46