He replied:

All praise is due to Allah, Lord of the worlds.

Yes, the deceased can hear, in general, as is established in the two Sahīh collections from the Prophet (peace and blessings be upon him), who said:

“He hears the sound of their sandals as they turn away from him.”

It is also established that the Prophet (peace and blessings be upon him):

“Left those slain at Badr for three days, then came to them and said, ‘O Abū Jahl ibn Hishām, O Umayyah ibn Khalaf, O ‘Utbah ibn Rabī‘ah, O Shaybah ibn Rabī‘ah! Have you found what your Lord promised you to be true? For I have found what my Lord promised me to be true.’ ‘Umar—may Allah be pleased with him—heard this and said, ‘O Messenger of Allah, how can they hear, and how could they answer, when they have decomposed?’ He replied, ‘By Him in Whose Hand is my soul, you hear what I say no better than they do, but they are unable to answer.’”

He then ordered that they be dragged into the well of Badr. Likewise, the two Sahīh collections relate from ‘Abdullāh ibn ‘Umar:

“The Prophet (peace and blessings be upon him) stood by the well of Badr and said, ‘Have you found what your Lord promised you to be true?’ He also said, ‘They now hear what I am saying.’”

It is also established through several reports in the two Sahīh collections that he would instruct people to greet the inhabitants of the graves, saying:

“Say: ‘Peace be upon you, inhabitants of these dwellings, believers and Muslims. We will, if Allah wills, join you. May Allah have mercy upon those among us and you who have gone ahead and those who are to follow. We ask Allah for well-being for ourselves and for you. O Allah, do not deprive us of the reward for them, do not subject us to trials after them, and forgive us and them.’”

This is an address to them, and only someone who hears is addressed. Ibn ‘Abd al-Barr related from the Prophet (peace and blessings be upon him)