1, Water was added to aqueous solution of a certain salt with concertation of 20%, which resulted in a 20% mass increase of the solution Part of the water was then evaporated from the resulting solution and its mass decreased by 20%. What is the current concentration of this solution? 2.The height of the isosceles trapezoid ABCD from the vertex D of the obtuse angle divides the longer base into sections AE and EB of 3 cm and 13 cm respectively. The triangle AED is isosceles. Calculate the area of the trapezoid ABCD.

answer: 12

step-by-step explanation:

the answer is b

a.) list the factors of 40.

1/2/4/5/8/10/20/40

b.) list the factors of 40 that represent the number of cans that could be on each shelf.

5

c.) how many different arrangements of cans are possible?

just one because if you put more on one shelf you will go way over 40 and the cabinet will probably break.

d.) what are the possible arrangements of the cans?

put 5 cans on each self to reach 40 cans in total.

e.) which arrangement uses all the shelves?

5 because you can put 5 cans on each shelf, and since there are 8 shelfs you are equally going to get 40 cans.