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
Pavlova-9 [17]
3 years ago
5

Only 20 plant species, such as rice, corn,and barely, make up the main sources of food for the entire human population.

Chemistry
2 answers:
Flauer [41]3 years ago
8 0

Answer:

D

Explanation:

to enhance the survival

riadik2000 [5.3K]3 years ago
7 0

Answer:

I believe it would be D, to enhance the survival rate.

Explanation:

You might be interested in
Heating by direct contact between particles is called ____________​
nataly862011 [7]

Answer:

conduction

Explanation:

Conduction is the transfer of heat between substances that are in direct contact with each other. ... Conduction occurs when a substance is heated, particles will gain more energy, and vibrate more. These molecules then bump into nearby particles and transfer some of their energy to them.

3 0
2 years ago
5. Can you determine the number of neutrons in the nucleus of an atom by looking at the element's average atomic mass and the at
Shkiper50 [21]

Answer:

No you can't

Explanation:

The atomic number is the amount of protons in element's nucleus, that's one reason why. The second reason is that the atomic mass is protons and neutrons combined, their estimated value, which doesn't show how much neutrons are in an element. It does show combined, but not specifically neutrons

7 0
2 years ago
A graduated cylinder was filled with water to the 25.0 mL mark and weighed. Its mass was 105.5g. An object made of an unknown me
Marta_Voda [28]
The answer <span>is <span>8.9 g/mL</span>.</span>

The density (D) is <span>equal to mass (m) divided by volume (V): D = m/V

Let's find the mass of the object:
m = 156 g - 105.5 g = 50.5 g

Let's find the volume of the volume:
V = 30.7 mL - 25 mL = 5.7 mL

The density is:
D = m/V = 50.5 g  / 5.7 mL = 8.9 g/mL</span>
6 0
3 years ago
What was a Parthian battery?
timama [110]

Answer:

Scientists believe the batteries (if that is their correct function) were used to electroplate items such as putting a layer of one metal (gold) onto the surface of another (silver), a method still practiced in Iraq today.

Explanation:

8 0
3 years ago
A rectangular corral of widths Lx = L and Ly = 2L contains seven electrons. What is the energy of (a) the first excited state, (
DiKsa [7]

Answer:

See explaination

Explanation:

The invariant mass of an electron is approximately9. 109×10−31 kilograms, or5. 489×10−4 atomic mass units. On the basis of Einstein's principle of mass–energy equivalence, this mass corresponds to a rest energy of 0.511 MeV.

Check attachment for further solution to the exercise.

3 0
2 years ago
Other questions:
  • Which medium allows sound to travel faster, air or water?
    6·2 answers
  • The solubility of nitrogen gas at 25°C and a nitrogen pressure of 522 mmHg is 4.7 × 10 –4 mol/L. What is the value of the Henry'
    13·1 answer
  • The reaction below is at dynamic equilibrium. mc004-1.jpg Which statement is true for the equilibrium system? The concentration
    13·2 answers
  • What is force and it's so unit?<br>​
    14·1 answer
  • A 3.50 amp power supply is used to deposit chromium from a solution of CrCl3. How long will it take to deposit 100.0 grams of ch
    11·1 answer
  • describe the general trend in electronegativity as metals in group 2 on the periodic table are concidered in order of increasing
    13·1 answer
  • 6.50 g of a certain Compound x, known to be made of carbon, hydrogen and perhaps oxygen, and to have a molecular molar mass of 1
    7·1 answer
  • After watching the morning news, roommates Kelly and Rob argued about whether or not a man on trial should have been sentenced t
    10·2 answers
  • Mixing baking soda and vinegar is an example of an endothermic reaction. This means...
    5·2 answers
  • In a chemical hot pack, iron powder and oxygen react to form iron oxide in the presence of a catalyst. This reaction causes the
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!