Which rotation about its center will carry a regular decagon onto itself?
a. 54
b. 162
c. 198
d. 252
!

D.252

Step-by-step explanation:

In this question, We have to find which rotation about its center will carry a regular decagon onto itself?

A decagon : 10 sided polygon

As we know, a full rotation can be 360°.

For a decagon: 360/10 =36

For a decagon, any multiple of 36 can map onto itself.

In our options only 252 is the multiple of 36.

So, correct answer is option D 252

rick has $1400 and sally has $1500

step-by-step explanation:

to find amount of money rick has after 10 years :

principal = $1000 , time = 10 years , rate = 4% annually

to find amount of money sally has after 10 years :

her friend gives to pay her $50 per year, therefore money she has after 10 years = 50 × 10 = $500

also, sally gets $1000 after 10 years,

therefore, total amount of money sally has after 10 years = 500 + 1000 = $1500

so, after 10 years : rick has $1400 and sally has $1500

$649.60

step-by-step explanation: