What are Jordan's and the Buchanans' reactions to Myrtle's death in The Great Gatsby?

At first, asstands over
Myrtle's dead body, he is "motionless," and he seems to be in shock.  After all,
Myrtle had seemed so vital, so very alive when she was living, and her death is a rather
gruesome one.  When he hearssay that he knows exactly what kind of car it was that hit
Myrtle,says,

I saw the wad of muscle back of his shoulder
tighten under his coat.  He walked quickly over to Wilson and, standing in front of him, seized
him firmly by the upper arms.  

Tom orders Wilson to pull
it together, and then he tries to quietly explain that the car he was driving earlier, the car
that killed Myrtle, was not his car and that he'd only just arrived at the scene.  He also tells
Wilson that he had just been bringing him his little blue coupe that he'd been promising Wilson
for months: a lie.  Once he is confident that he is no longer under any suspicion, he whispers
to Nick, "'Let's get out.'"  On their way home, Tom "sob[s]" and "tears
were overflowing down his face."  He believeskilled Myrtle.

When they
reach the Buchanans' house, Tom offers to call Nick a taxi, and Nick says he'll wait outside. 
Thenputs her hand on Nick's arm and asks, "'Won't you come in, Nick?'" as though she
wants to continue the evening as though a woman hasn't just been killed.  She laments the loss
of the night, saying, "'It's only half-past nine,'" but Nick suddenly finds he cannot
stand to be with any of them right now, including her.  "She must have seen something of
this in [his] expression, for she turned abruptly away and ran up the porch steps into the
house."  She might be cold and callous, but she's also quite proud.

Of
's response to hitting Myrtle with the car, Gatsby tells Nick,

'Daisy stepped on it.  I tried to make her stop, but she couldn't, so I pulled on the
emergency brake.  Then she fell over into my lap and I drove on.'

It's telling that Daisy's first response is not to stop and check
on the well-being of the woman she hit.  Instead, her first impulse seems to be to get away as
quickly as possible.  The fact that she cries seems to have more to do with her own feelings of
upset, rather than anything like sorrow for the woman she killed; this is corroborated by what
Nick sees through the window of the Buchanans' home: Tom and Daisy sitting and talking and
eating, appearing as though they are "conspiring together" -- Daisy isn't crying
now.