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!

step-by-step explanation:

graph using a few selected

x         y

-1       15

0         6

1         2.4

2       0.96

p

step-by-step explanation:

fabric (square meters)                   cloaks

7                                                           21

4/3                                                         4

step-by-step explanation:

we are told that harry needs 2 square meters of fabric for every 6 wizard cloaks he makes.

1. first of all we will find how many cloaks can be made from 1 square meter of fabric by dividing 6 by 2.

we can see that 3 cloaks can be made from 1 square meter of fabric. now we will multiply 3 by 7 to find number of cloaks made from 7 square meters of fabric.

therefore, harry will make 21 cloaks from 7 square meters of fabric.

2. let us find how many square meters of fabric will be needed to make 4 cloaks.

first of all we will find fabric needed for 1 cloak by dividing 2 by 6.

we can see that fabric needed for 1 cloak is   square meter. now we will multiply   by 4 to find fabric needed for 4 cloaks.