Step-by-step explanation:
Larval mosquitoes breath through trachea in their siphons. This is a structure analogous to the snorkel on a diesel electric submarine. It allows for gas exchange with the atmosphere while the remainder of the insect is submerged. The opening of the siphon is hydrophobic so it won’t get wet and blocked by water. This works well to keep the siphon and the trachea open under normal conditions. Oil when poured on water forms a thin film. When there are mosquitos in that water, when their siphons contact the oil layer, the oil wets and blocks their siphons and suffocates the mosquitoes. This works against most, but not all mossies, as evolution is an amazing process. Some mosquitoes (Mansonia, Coquilletidia) have a siphon designed to penetrate the air vessels in aquatic plants and they don’t need to come to the surface to breath like other mossies. So oil won’t work on these genera.
Answer:
Tickets sold:
VIP 
$17 tickets 
$21 tickets 
Step-by-step explanation:
Let x be the number of VIP tickets.
If ten times as many $17 tickets were sold as VIP tickets, then the number of $17 tickets is
If the number of $17 tickets sold was 57 more than the sum of the number of $21 tickets and VIP tickets, then
and the number y of $21 tickets is 
Amounts earned:
VIP tickets 
$17 tickets 
$21 tickets 
Total 
The sales of all three kinds of tickets would total $51,471, so

Tickets sold:
VIP 
$17 tickets 
$21 tickets 
Answer:
-7, then -13, then -19
Step-by-step explanation:
Plug in x values to get y.
y = -2(0) - 7
y = 0 - 7
y = -7
y = -2(3) - 7
y = -6 - 7
y = -13
y = -2(6) - 7
y = -12 - 7
y = -19
Hope this helps. :0)
Using proportions, it is found that the number of islands that each member will have to visit is given by:
c. 19 islands.
<h3>What is a proportion?</h3>
A proportion is a fraction of a total amount, and the measures are related using a rule of three.
In this problem, there are 684 islands, and 36 members, hence the number of islands per member is given by:
n = 684/36 = 19.
Which means that option c is correct.
More can be learned about proportions at brainly.com/question/24372153
#SPJ1
9x⁹ - 90x⁸ - 351x⁷
What do each of these numbers have in common?
They ALL have 9x⁷ in them!
So, divide each one of these by 9x⁷
9x⁹ ÷ 9x⁷ = 9x²
-90x⁸ ÷ 9x⁷ = -9x
-351x⁷ ÷ 9x⁷ = -39
So, factorized completely, it is :
9x² - 9x - 39
~Hope I helped!~