Final answer:
A bad actor would indeed be able to double-spend a Bitcoin by performing a 51% attack if they control more than 50% of the total hashing power, which is true.
Step-by-step explanation:
The statement that a bad actor would be able to double-spend a Bitcoin if they controlled more than 50% of the total hashing power maintaining the blockchain is indeed true. This scenario is known as a 51% attack. The reason this is possible is that Bitcoin transactions are confirmed by miners who contribute their computational power to the network to validate transactions and add them to the blockchain, which is a decentralized digital ledger. Having more than half of the hashing power gives a miner or a group of miners the ability to manipulate the blockchain by creating a separate version of it where they can reverse their own transactions. This could potentially allow them to spend their Bitcoins more than once.
However, it's worth noting that achieving and sustaining a 51% attack on a well-established cryptocurrency like Bitcoin is incredibly difficult and costly. The amount of computational power and energy required is substantial, and maintaining control without being detected and counteracted by the network is challenging.