Norma earns $22 per hour. she donates 5% of her wages to her favorite charity. if she wants to have at least $748 left after her donation, how many hours (h) must she work? (round the number of hours up to the next whole hour.)

She must work for at least 36 hours

Step-by-step explanation:

* Lets explain how to solve the problem

- Norma earns $22 per hour

- She donates 5% of her wages to her favorite charity

- She wants to have at least $748 left after her donation

- We want to find how many hours (H) she must work to have

 this amount

- Assume that she will work for H hours

∵ She earns $22 per hour

∴ Her wages = 22 × H = 22H

- She donates 5% of her wage

∴ Her donate =

- She wants to have at least $748 left after her donation

∵ The money left = her wage - her donate

∴ The money left  = 22H - 1.1H = 20.9H

- She wants to have at least $748

∵ The money left ≥ $748

∴ 20.9H ≥ 748

- Divide both sides by 20.9

∴ H ≥ 35.789

∴ She must work for at least 36 hours

the value of v.w= -12.

step-by-step explanation:

we are given three vector r,v and w as:

r = < 5, -5, -2> ; v = < 2, -8, -8> ; w = < -2, 6, -5>

we know that r,v and w could also be represented as:

r=5i-5j-2k

v=2i-8j-8k

and w= -2i+6j-5k

where i,j and k are the unit vectors of x,y and z-axis respectively.

also we know that it has the following property:

i.i=1 ; j.j=1; k.k=1

and i.=j.i=i.k=k.i=j.k=k.j=0

i.e. when we multiply two vectors or we find it's dot product we need to only multiply the components of x coordinates with each other; y with each other and z with each other.

hence, v.w= (2i-8j- -2i+6j-5k)

                  = 2×(-2)+(-8)×(6)+(-8)×(-5)

                  = -4-48+40

                  = -12

hence, v.w= -12

do you have a picture of the table