Explanation

China launched the CR450, the fastest high-speed train, reaching 450 km/h in tests and 400 km/h commercially.

It improves on the CR400 Fuxing, featuring advanced technology for speed, energy efficiency, and passenger comfort.

The train supports China’s goal to expand its rail network to 70,000 km by 2035.

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Explanation

China launched the CR450, the fastest high-speed train, reaching 450 km/h in tests and 400 km/h commercially.

It improves on the CR400 Fuxing, featuring advanced technology for speed, energy efficiency, and passenger comfort.

The train supports China’s goal to expand its rail network to 70,000 km by 2035.

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Explanation

Russia has developed an mRNA vaccine for cancer patients.

The vaccine is expected to be released in early 2025.

The vaccine will be free for eligible Russian cancer patients.

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Explanation

in the early 1950s, the first successful vaccine was created by US physician Jonas Salk.

Salk tested his experimental killed-virus vaccine on himself and his family in 1953

First used Salk vaccine in 1955 ( in activated)

while 

A live attenuated (weakened) oral polio vaccine developed by Dr. Albert Sabin and first used in 1961.

Israel launched a polio vaccine drive after 1988 in April 2022

Explanation

Microsoft was founded on April 4, 1975.

It was founded by Bill Gates and Paul Allen in Albuquerque, New Mexico.