1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Andrei [34K]
2 years ago
9

Why must a new flu vaccine be manufactured annually?

Chemistry
1 answer:
mafiozo [28]2 years ago
7 0

Answer:

D or A

<em>But I do know...</em>

It's because new strains of the virus are constantly appearing and evolving, so the vaccine must change along with them.

You might be interested in
Select the correct answer. Given: 2Al + 6HCl → 2AlCl3 + 3H2 If the chemical reaction produces 129 grams of AlCl3, how many grams
ivann1987 [24]

The reaction produces 2.93 g H₂.

M_r:                        133.34  2.016

        2Al + 6HCl → 2AlCl₃ + 3H₂

<em>Moles of AlCl₃</em> = 129 g AlCl₃ × (1 mol AlCl₃/133.34 g AlCl₃) = 0.9675 mol AlCl₃

<em>Moles of H₂</em> = 0.9675 mol AlCl₃ × (3 mol H₂/2 mol AlCl₃) = 1.451 mol H₂

<em>Mass of H₂</em> = 1.451 mol H₂ × (2.016 g H₂/1 mol H₂) = 2.93 g H₂

7 0
3 years ago
Is the chemical equation balanced?<br><br> Yes or no
Strike441 [17]
I think it is not so no
6 0
2 years ago
Read 2 more answers
Which list of elements is arranged in order of increasing electronegativity?
muminat
K, ca, sc is the right answer. Take a look at table S of your chemistry reference table. 
6 0
3 years ago
Read 2 more answers
What are three ways lakes can form?
quester [9]
Just choose 3

1) Lakes can form in hollows left by meteorite impacts (e.g. Clearwater Lakes, Quebec, Canada).

2) Lakes can form in the craters formed by volcanoes (e.g. Crater Lake, Oragon)

3) Lakes can form when a river is damed by a natural rock fall or man (e.g. Lake Mede)

4) Lakes can form where glaciers have scooped out the rock from the floor of a valley (e.g. Lake Geneva)

5) Lakes can form where block faulting lowers the land (e.g. lake Baikal)

6) lakes can form in natural depressions in the land (e.g. Lake Victoria)
4 0
3 years ago
Why does tap water or pool water typically test positive for the presence of chlorine
sweet-ann [11.9K]
Pool water contains chlorine to keep it sanitary
<span />
6 0
3 years ago
Other questions:
  • Balance this equation. If a coefficient of "1" is required, choose "blank" for that box. ____CO +____ O2 → ____CO2
    11·2 answers
  • In the reaction, A -----&gt; Products, the rate constant is 3.6 x 10^−4 s−1. If the initial concentration of A is 0.548 M, what
    12·1 answer
  • A 115.0-g sample of oxygen was produced by heating 400.0 g of potassium chlorate.2KClO3 Right arrow. 2KCI + 3O2What is the perce
    8·1 answer
  • 1. If you have 25% radioactive parent atoms in a mineral crystal, and 75% daughter atoms, how many half-lives have passed?
    10·1 answer
  • You carefully drop a stone into a beaker full of water. The stone sinks to the bottom and water spills out. What can you say abo
    11·1 answer
  • 1) A) Balance the following equation:
    15·1 answer
  • Which statement about pollination is
    11·2 answers
  • A system fitted with a piston expands when it absorbs 53.1 ) of heat from the surroundings. The piston is working against a pres
    5·1 answer
  • Plzzzz helppppp meeee
    10·1 answer
  • Look at the diagram. De both lemas and humans have the traits listed at point D? Explain your reasoning​
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!