Answer:
21 diamonds.
Step-by-step explanation:
1 bracelet = 7 diamonds
3 bracelet= ? diamonds
All we have to do is multiply 3 by 7 to get the number of diamonds Jen have with three bracelets.
3 x 7 = 21
72 minutes
We require their hourly rate of work
Maria cleans
the house in 1 hour
Sasha cleans
of the house in 1 hour
let x be the time it takes both to clean the house
+
= 
multiply through by 6x
3x + 2x = 6
5x = 6 ⇒ x = 
Together they can clean the house in 72 minutes
To find the lateral area of a cone, use this formula:

where r is the radius (in this case, 11) and h is the height (in this case, 26)
Try plugging the values in. If you need additional help, feel free to ask!