The de broglie wavelength of an electron with a velocity of 7.40 × 106 m/s is m. the mass of the electron is 9.11 × 10-28 g.

The de Broglie wavelength has an equation written as:

λ = h/mv
where
λ is the de Broglie wavelength
h is the Planck's constant equal to 6.63×10⁻³⁴ J·s
m is the mass
v is the velocity

Substituting the values (make sure to use SI units):

λ = (6.63×10⁻³⁴ J·s)/(9.11×10⁻²⁸ g * 1 kg/1000 g)(7.40×10⁶ m/s)
λ = 9.835×10⁻¹¹ m

It would be (at) + cu (s)

The  grandmother cell  is a hypothetical  neuronthat represents a complex but specific concept or object.[1]  it activates when a person "sees, hears, or otherwise sensibly discriminates"[2]  a specific entity, such as his or her grandmother. the term was in use at least as early as 1966 amongst staff and students in the department of experimental psychology, university of cambridge, england. a similar concept, that of the  gnostic neuron, was proposed two years later