A shark pup has a pointed fin. Its mother also had a pointed fin, but its father had a rounded fin. Which of these statements explains why the shark pup has a pointed fin?
a
The shark pup inherited one copy of the gene for fin shape from its mother and one copy
from its father. That gene combination instructs for proteins that connect in ways that
make its fin pointed.
b
The shark pup inherited one copy of the gene for fin shape from its mother and one copy
from its father. Those genes connect together to make its fin pointed.
с
The shark pup inherited its copies of the gene for fin shape from its mother and not from its
father. Those genes connect together to make its fin pointed.
d
The shark pup inherited its copies of the gene for fin shape from its mother and not from its
father. Just like its mother's genes, those genes instruct for proteins that connect in ways
that make its fin pointed.

Consider the particle-in-a-box problem in 1d. a particle with mass m is confined to move freely between two hard walls situated at x = 0 and x = l. the potential energy function is given as (a) describe the boundary conditions that must be satisfied by the wavefunctions ψ(x) (such as energy eigenfunctions). (b) solve the schr¨odinger’s equation and by using the boundary conditions of part (a) find all energy eigenfunctions, ψn(x), and the corresponding energies, en. (c) what are the allowed values of the quantum number n above? how did you decide on that? (d) what is the de broglie wavelength for the ground state? (e) sketch a plot of the lowest 3 levels’ wavefunctions (ψn(x) vs x). don’t forget to mark the positions of the walls on the graphs. (f) in a transition between the energy levels above, which transition produces the longest wavelength λ for the emitted photon? what is the corresponding wavele

Física: un futbolista patea hacia el arco con una velocidad de 15m/ah, calcular: a)el alcance para un ángulo de tiro de 25? , b) el tiempo que el balón permanece en el aire.

Aresistor with an unknown resistance is connected in parallel to a 9 ω resistor. when both resistors are connected in parallel to an emf source of 21 v, the current through the unknown resistor is measured with an ammeter to be 4 a. what is the resistance of the unknown resistor? answer in units of ω.