Harem Lord System: Post Apocalyptic World - Chapter 17: I Doubt That

Although Leng Ruoxue is born mentally challenged, she is the most beloved granddaughter of the number one general in the Eastern Lake Nation. She is despised by her fiancé and schemed against by her love rival. However, she is reborn as a powerful soul. This is a fantasy world, and also a world where the strong are respected. Cultivation, alchemy, weapon refinement, beast taming—the once foolish young miss has transformed into a stunning genius. Pill refinement and weapon refinement are all child's play. Heaven Grade medicinal pill? Even my pets won't turn an eye to it. Heavenly Treasure? I have the space to grow my own. Sacred artifact? Sorry, that's too low a level. I only know how to refine divine artifacts. Beast taming? My beasts deliver themselves to my doorstep.

A scientific genius named Thomas Harrier was transmigrated to an imperial prince body after a car accident that took his life. He found out that he is in a world similar to our own with a timeline akin to early twentieth century. The body that he is occupying was the imperial prince of a failing empire who suddenly rose to power after a successful assassination attempt of his father. Unaware that the attack is just the beginning of what is to come. He faces many challenges throughout. Will Thomas Harrier be able to live his second life in peace while running an empire and getting it back to its former glory? Or will he succumb into a conspiracy lurking within the country's borders?

Expect some:

Cold war era techs.

Super battleship with advanced electronics, propulsion, and fire control systems?
Helicopters?
Missiles?
Modern medicines and equipment?
AC-130?
A nuke?
Challenger or Abrams or Leopard?
F-4 Phantom or MIG-21?
Colored TV's.

Everything!!!

PS. Cover not mine, I just found it on google.

She married a driver she just met. However, the last thing that had ever come to her expectation was that her bridegroom was no other than the most mysterious billionaire in the city. This marriage brought her baby twins. Thus, she worked harder to support this family. She was the queen of the entertainment circle. When she met the king who dominated the business world, she finally knew her husband’s true identity.

Wake up and an unknown door has appeared in your home… Behind each door is a completely unfamiliar world.In the nightmare world, Jiang Cheng relays the news from the Hunk to the Fatty, adding his own spin to the story.The Fatty almost cried in fear hearing it.“My whole family will be strung upside down for blood-letting if I die here?”“That’s what I heard.”“Then, how come you don’t look scared at all?” The fatty widened his eyes.Jiang Cheng turned around and replied in a very formal tone, “Because I’m an orphan.”