Answer:
(i),(ii) and (iv)
Explanation:
Villi are finger-like outgrowths of the human intestine.
The main role of villi is to amplify surface area for rapid absorption of digested food. They have very tiny walls; the role of these walls is to pass digested nutrients through diffusion. These are directly connected to the blood vessels. Thus, the circulating blood can carry these nutrients away.
The correct answer is the first option.
The three
states of matter are solid, liquid and gas phase. The solid has a more definite
shape and volume. The particles are locked into place. It cannot be further
compressed due to the bond that exists between the molecules. The kinetic
energy of the molecules is close to none because the molecules are so close and
so compact with each other. For liquids, it has a medium shape and volume. The
particles can move or slide past each other due to the small space available
for movement. It cannot be compressed further due to the repulsive forces that
acts between them. The kinetic energy is medium. For gases, it has no shape and
volume because the particles can move freely from one other. Their collisions
are rare due to the distance between them. The kinetic energy of the molecules
is high because there is room for movement. It can be compressed easily.
Answer:
38 kg/m³
0.038 g/mL
Explanation:
Volume of a cube is the side length cubed.
V = s³
Given s = 0.65 m:
V = (0.65 m)³
V ≈ 0.275 m³
The mass is 10.5 kg. The density is the mass divided by volume:
ρ = (10.5 kg) / (0.275 m³)
ρ ≈ 38 kg/m³
Or:
ρ ≈ 0.038 g/mL
1 mole of NaHCO3 = 84g
1 mole of NaHCO3--------------84g
x moles of NaHCO3----------0,50g
x = 0,00595 moles of NaHCO3
0,00595 moles of NaHCO3----------in--------250ml
x moles of NaHCO3-------------------in-----------1000ml
x = 0,0238 moles of NaHCO3
answer: the molar <span>concentration of NaHCO3 is 0,0238mol/l</span>