Which condition may cause farsightedness?
an eyeball that is too long
a cornea that is not curved enough
an iris that cannot expand
a pupil that is too wide

The correct answer is a cornea that is not curved sufficiently.

Explanation:

Hyperopia or farsightedness refers to a condition or state of vision in which far off objects are generally seen evidently, however, the close objects do not come into focus properly. The condition takes place in case if the cornea has too little curvature or if the eyeball is too short, thus, the light getting inside the eye does not get focused accurately.

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.